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ipa_netgroups: Lowercase key to htable #59
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Fixes: https://fedorahosted.org/sssd/ticket/3116 We lowercase the search key when storing entries into the hash table, but do not do it when we search for them. As a result we were not able to find netgroup by DN.
There is a missing test => Change requested |
before the patch:
After the patch:
So the netgroup can be resolved, but is it correct that the netgroup member is listed twice? |
On (20/10/16 01:21), Jakub Hrozek wrote:
|
On Thu, Oct 20, 2016 at 01:40:15AM -0700, lslebodn wrote:
Same as the reproducer in the ticket. But the point is, is it ever OK to |
On (20/10/16 02:20), Jakub Hrozek wrote:
Here is a hierarchy based on descition in ticket So getent netgroup shoudl return for ng1 -> just a "(-,user1,-)" This is exactly a reason why I require to write a test for each bugfix. LS |
On Thu, Oct 20, 2016 at 02:55:12AM -0700, lslebodn wrote:
Well, a different bug is fixed (and Michal was arguing there are two
OK, then my setup is different, sorry: |
On (20/10/16 02:58), Jakub Hrozek wrote:
LS |
On (20/10/16 02:58), Jakub Hrozek wrote:
LS |
Lukas: The ticket 3116 was closed as duplicate by you. I was always saying that it is not duplicate. I even said that in order to solve them properly we need to first solve 3116 and then 3117 (I set 3117 as blocked by 3116). Because this patch is for 3116 and not for 3117, I put 3116 to the commit message. I was not able to reproduce 3117 with master anymore. I am reopening this PR. Feel free to reopen the 3116 ticket. This ticket is quite simple. We lowercase the key to htable when we store the entries, but we do not lowercase the keys that we use to search the entries. Which is IMO totally obvious bug. Btw. by not fixing this, we make other potential bugs with nested netgroups totally invisible even for manual testing and that is keeping us from discovering/fixing those. |
I am glad that ticket #3117 cannot be reproduced. Please close it. The ticket #3116 is one of the best examples how should ticket not look like. Anyway fix is wrong. Ipa provider is not case insensitive. And we do not lowercase anything for netgroups in ldap provider. Closing this PR as rejected. It will be much simpler to have a conversation about new patch in new PR |
IPA does not allow other then lower cased netgroup names. ipa netgroup-addNetgroup name: WAAAAdded netgroup "waaa"Netgroup name: waaa I do not see reason to open a new PR with the same patch. Reopening. |
And yes, there are differences between plain LDAP and IPA providers. The netgroup code is completely different. It may be good to unify the two, but it is not purpose of this patch. |
On Thu, Oct 20, 2016 at 05:04:20AM -0700, mzidek-rh wrote:
Maybe it would be good to explain why do we need to lowercase anything? |
On (20/10/16 05:08), Jakub Hrozek wrote:
LS |
Part of the key is the attribute name. My guess is that the lowercaseing before storing to the hash table is to make sure that the attribute name case will not play any role. |
We can discuss even in closed PR, but better would be move discussion on sssd-devel. |
Hi, I am reopening this ticket, because FreeIPA UQE have a test. Btw. I can change the patch to not lowercase the key in the first place (while creating the entry in the table). The point is the cases need to be constant. I am just not sure if that can brake something. We do not have extensive upstream tests for FreeIPA and netgroups and the lowercasing seem to be intentional, even though I do believe it is just result of unnecessary normalization. |
It looks like you forgot how to read. this PR is completely wrong. Subject and fix are wrong. |
Please open new PR with correct ticket attached. |
Well, changing the ticket is a detail, we can change the ticket wording if necessary. I would like to get some comments on the lowercasing and if we want to go with the solution or if we want to skip the lowercasing when the entry is created (or some other solution). I do not think that the discussion need to be moved from this PR. |
There nothing to discuss here. And If you are not sure about solution then it's better to discuss about possible solution on sssd-devel. The discussion about bug can be done even without patch. |
Please do not reopen this PR anymore. Mails are much more suitable for such discussion. |
FYI: there is already better ticket |
While debugging rhbz#1396912 some deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). The removal of those functions we lose some debug messages, which is the least of problems now. Also instead of re-setting the watchdog timeout in case of time-shift (please, see b8ceaeb for more info), let's just re-set the timer's time. Along with this commit, the function to teardown the watchdog has been removed as it's not used anymore. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 some deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). The removal of those functions we lose some debug messages, which is the least of problems now. Also instead of re-setting the watchdog timeout in case of time-shift (please, see b8ceaeb for more info), let's just exit the let the monitor restart the process. A proper fix for the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler will be done inside the fd handler in a safe way. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by _exit(). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by _exit(). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by _exit(). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by _exit(1). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM) (or _exit(1) considering the cases where setting up the process group during the server_setup() has failed). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 SSSD#1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 SSSD#2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 SSSD#3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 SSSD#4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 SSSD#5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 SSSD#6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM) (or _exit(1) considering the cases where setting up the process group during the server_setup() has failed). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 #1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 #2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 #3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 #4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 #5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 #6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 #7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 #8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 #9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 #10 <signal handler called> #11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 #12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 #13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 #14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 #15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 #16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 #17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 #18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 #19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 #20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 #21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 #22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 #23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 #24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 #25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 #26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 #27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 #28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 #29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 #30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 #31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 #32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 #33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 #34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 #35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 #36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 #37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 #38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 #39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 #40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 #41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 #42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 #43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 #44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 #45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 #46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 #47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 #48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 #49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 #50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 #51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 #52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 #53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 #54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 #55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 #56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 #57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 #58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 #59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 #60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com> Reviewed-by: Pavel Březina <pbrezina@redhat.com> Reviewed-by: Jakub Hrozek <jhrozek@redhat.com> Reviewed-by: Simo Sorce <simo@redhat.com>
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM) (or _exit(1) considering the cases where setting up the process group during the server_setup() has failed). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 #1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 #2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 #3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 #4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 #5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 #6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 #7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 #8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 #9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 #10 <signal handler called> #11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 #12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 #13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 #14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 #15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 #16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 #17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 #18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 #19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 #20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 #21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 #22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 #23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 #24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 #25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 #26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 #27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 #28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 #29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 #30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 #31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 #32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 #33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 #34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 #35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 #36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 #37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 #38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 #39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 #40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 #41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 #42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 #43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 #44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 #45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 #46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 #47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 #48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 #49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 #50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 #51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 #52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 #53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 #54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 #55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 #56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 #57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 #58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 #59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 #60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com> Reviewed-by: Pavel Březina <pbrezina@redhat.com> Reviewed-by: Jakub Hrozek <jhrozek@redhat.com> Reviewed-by: Simo Sorce <simo@redhat.com> (cherry picked from commit e6a5f8c)
While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM) (or _exit(1) considering the cases where setting up the process group during the server_setup() has failed). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 #1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 #2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 #3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 #4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 #5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 #6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 SSSD#7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 SSSD#8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 SSSD#9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 SSSD#10 <signal handler called> SSSD#11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 SSSD#12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 SSSD#13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 SSSD#14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 SSSD#15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 SSSD#16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 SSSD#17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 SSSD#18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 SSSD#19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 SSSD#20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 SSSD#21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 SSSD#22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 SSSD#23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 SSSD#24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 SSSD#25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 SSSD#26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 SSSD#27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 SSSD#28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 SSSD#29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 SSSD#30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 SSSD#31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 SSSD#33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 SSSD#34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 SSSD#35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 SSSD#36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 SSSD#37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 SSSD#38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 SSSD#39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 SSSD#40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 SSSD#41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 SSSD#42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 SSSD#43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 SSSD#44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 SSSD#45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 SSSD#46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 SSSD#47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 SSSD#48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 SSSD#49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 SSSD#50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 SSSD#51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 SSSD#52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 SSSD#53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 SSSD#54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 SSSD#55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 SSSD#56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 SSSD#57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 SSSD#58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 SSSD#59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 SSSD#60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com> Reviewed-by: Pavel Březina <pbrezina@redhat.com> Reviewed-by: Jakub Hrozek <jhrozek@redhat.com> Reviewed-by: Simo Sorce <simo@redhat.com> (cherry picked from commit e6a5f8c) (cherry picked from commit 0606a71)
Fixes:
https://fedorahosted.org/sssd/ticket/3116
We lowercase the search key when storing
entries into the hash table, but do not
do it when we search for them. As a result
we were not able to find netgroup by
DN.