-
Notifications
You must be signed in to change notification settings - Fork 37
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
RFE: record the path of files accessed using the *at(2) syscalls #9
Comments
As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported a lockdep splat [1] (false positive) that we can fix by releasing the spinlock before calling icmp_send() from ip_expire() This is a false positive because sending an ICMP message can not possibly re-enter the IP frag engine. [1] [ INFO: possible circular locking dependency detected ] 4.10.0+ #29 Not tainted ------------------------------------------------------- modprobe/12392 is trying to acquire lock: (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] spin_lock include/linux/spinlock.h:299 [inline] (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] __netif_tx_lock include/linux/netdevice.h:3486 [inline] (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 but task is already holding lock: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock include/linux/spinlock.h:299 [inline] (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&(&q->lock)->rlock){+.-...}: validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] ip_defrag+0x3a2/0x4130 net/ipv4/ip_fragment.c:669 ip_check_defrag+0x4e3/0x8b0 net/ipv4/ip_fragment.c:713 packet_rcv_fanout+0x282/0x800 net/packet/af_packet.c:1459 deliver_skb net/core/dev.c:1834 [inline] dev_queue_xmit_nit+0x294/0xa90 net/core/dev.c:1890 xmit_one net/core/dev.c:2903 [inline] dev_hard_start_xmit+0x16b/0xab0 net/core/dev.c:2923 sch_direct_xmit+0x31f/0x6d0 net/sched/sch_generic.c:182 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_resolve_output+0x6b9/0xb10 net/core/neighbour.c:1308 neigh_output include/net/neighbour.h:478 [inline] ip_finish_output2+0x8b8/0x15a0 net/ipv4/ip_output.c:228 ip_do_fragment+0x1d93/0x2720 net/ipv4/ip_output.c:672 ip_fragment.constprop.54+0x145/0x200 net/ipv4/ip_output.c:545 ip_finish_output+0x82d/0xe10 net/ipv4/ip_output.c:314 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 raw_sendmsg+0x26de/0x3a00 net/ipv4/raw.c:655 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:761 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 ___sys_sendmsg+0x4a3/0x9f0 net/socket.c:1985 __sys_sendmmsg+0x25c/0x750 net/socket.c:2075 SYSC_sendmmsg net/socket.c:2106 [inline] SyS_sendmmsg+0x35/0x60 net/socket.c:2101 do_syscall_64+0x2e8/0x930 arch/x86/entry/common.c:281 return_from_SYSCALL_64+0x0/0x7a -> #0 (_xmit_ETHER#2){+.-...}: check_prev_add kernel/locking/lockdep.c:1830 [inline] check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940 validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] __netif_tx_lock include/linux/netdevice.h:3486 [inline] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_hh_output include/net/neighbour.h:468 [inline] neigh_output include/net/neighbour.h:476 [inline] ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x960/0xcf0 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:657 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707 __read_once_size include/linux/compiler.h:254 [inline] atomic_read arch/x86/include/asm/atomic.h:26 [inline] rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline] __rcu_is_watching kernel/rcu/tree.c:1133 [inline] rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147 rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline] filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335 do_fault_around mm/memory.c:3231 [inline] do_read_fault mm/memory.c:3265 [inline] do_fault+0xbd5/0x2080 mm/memory.c:3370 handle_pte_fault mm/memory.c:3600 [inline] __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&q->lock)->rlock); lock(_xmit_ETHER#2); lock(&(&q->lock)->rlock); lock(_xmit_ETHER#2); *** DEADLOCK *** 10 locks held by modprobe/12392: #0: (&mm->mmap_sem){++++++}, at: [<ffffffff81329758>] __do_page_fault+0x2b8/0xb60 arch/x86/mm/fault.c:1336 #1: (rcu_read_lock){......}, at: [<ffffffff8188cab6>] filemap_map_pages+0x1e6/0x1570 mm/filemap.c:2324 #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] spin_lock include/linux/spinlock.h:299 [inline] #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] pte_alloc_one_map mm/memory.c:2944 [inline] #2: (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>] alloc_set_pte+0x13b8/0x1b90 mm/memory.c:3072 #3: (((&q->timer))){+.-...}, at: [<ffffffff81627e72>] lockdep_copy_map include/linux/lockdep.h:175 [inline] #3: (((&q->timer))){+.-...}, at: [<ffffffff81627e72>] call_timer_fn+0x1c2/0x820 kernel/time/timer.c:1258 #4: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock include/linux/spinlock.h:299 [inline] #4: (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201 #5: (rcu_read_lock){......}, at: [<ffffffff8389a633>] ip_expire+0x1b3/0x6c0 net/ipv4/ip_fragment.c:216 #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] spin_trylock include/linux/spinlock.h:309 [inline] #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_xmit_lock net/ipv4/icmp.c:219 [inline] #6: (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_send+0x803/0x1c80 net/ipv4/icmp.c:681 #7: (rcu_read_lock_bh){......}, at: [<ffffffff838ab9a1>] ip_finish_output2+0x2c1/0x15a0 net/ipv4/ip_output.c:198 #8: (rcu_read_lock_bh){......}, at: [<ffffffff836d1dee>] __dev_queue_xmit+0x23e/0x1e60 net/core/dev.c:3324 #9: (dev->qdisc_running_key ?: &qdisc_running_key){+.....}, at: [<ffffffff836d3a27>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 stack backtrace: CPU: 0 PID: 12392 Comm: modprobe Not tainted 4.10.0+ #29 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:52 print_circular_bug+0x307/0x3b0 kernel/locking/lockdep.c:1204 check_prev_add kernel/locking/lockdep.c:1830 [inline] check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940 validate_chain kernel/locking/lockdep.c:2267 [inline] __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] __netif_tx_lock include/linux/netdevice.h:3486 [inline] sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180 __dev_xmit_skb net/core/dev.c:3092 [inline] __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423 neigh_hh_output include/net/neighbour.h:468 [inline] neigh_output include/net/neighbour.h:476 [inline] ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268 expire_timers kernel/time/timer.c:1307 [inline] __run_timers+0x960/0xcf0 kernel/time/timer.c:1601 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:657 [inline] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707 RIP: 0010:__read_once_size include/linux/compiler.h:254 [inline] RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline] RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline] RIP: 0010:__rcu_is_watching kernel/rcu/tree.c:1133 [inline] RIP: 0010:rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147 RSP: 0000:ffff8801c391f120 EFLAGS: 00000a03 ORIG_RAX: ffffffffffffff10 RAX: dffffc0000000000 RBX: ffff8801c391f148 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000055edd4374000 RDI: ffff8801dbe1ae0c RBP: ffff8801c391f1a0 R08: 0000000000000002 R09: 0000000000000000 R10: dffffc0000000000 R11: 0000000000000002 R12: 1ffff10038723e25 R13: ffff8801dbe1ae00 R14: ffff8801c391f680 R15: dffffc0000000000 </IRQ> rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline] filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335 do_fault_around mm/memory.c:3231 [inline] do_read_fault mm/memory.c:3265 [inline] do_fault+0xbd5/0x2080 mm/memory.c:3370 handle_pte_fault mm/memory.c:3600 [inline] __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011 RIP: 0033:0x7f83172f2786 RSP: 002b:00007fffe859ae80 EFLAGS: 00010293 RAX: 000055edd4373040 RBX: 00007f83175111c8 RCX: 000055edd4373238 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f8317510970 RBP: 00007fffe859afd0 R08: 0000000000000009 R09: 0000000000000000 R10: 0000000000000064 R11: 0000000000000000 R12: 000055edd4373040 R13: 0000000000000000 R14: 00007fffe859afe8 R15: 0000000000000000 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
mipsxx_pmu_handle_shared_irq() calls irq_work_run() while holding the pmuint_rwlock for read. irq_work_run() can, via perf_pending_event(), call try_to_wake_up() which can try to take rq->lock. However, perf can also call perf_pmu_enable() (and thus take the pmuint_rwlock for write) while holding the rq->lock, from finish_task_switch() via perf_event_context_sched_in(). This leads to an ABBA deadlock: PID: 3855 TASK: 8f7ce288 CPU: 2 COMMAND: "process" #0 [89c39ac8] __delay at 803b5be4 #1 [89c39ac8] do_raw_spin_lock at 8008fdcc #2 [89c39af8] try_to_wake_up at 8006e47c #3 [89c39b38] pollwake at 8018eab0 #4 [89c39b68] __wake_up_common at 800879f4 #5 [89c39b98] __wake_up at 800880e4 #6 [89c39bc8] perf_event_wakeup at 8012109c #7 [89c39be8] perf_pending_event at 80121184 #8 [89c39c08] irq_work_run_list at 801151f0 #9 [89c39c38] irq_work_run at 80115274 #10 [89c39c50] mipsxx_pmu_handle_shared_irq at 8002cc7c PID: 1481 TASK: 8eaac6a8 CPU: 3 COMMAND: "process" #0 [8de7f900] do_raw_write_lock at 800900e0 #1 [8de7f918] perf_event_context_sched_in at 80122310 #2 [8de7f938] __perf_event_task_sched_in at 80122608 #3 [8de7f958] finish_task_switch at 8006b8a4 #4 [8de7f998] __schedule at 805e4dc4 #5 [8de7f9f8] schedule at 805e5558 #6 [8de7fa10] schedule_hrtimeout_range_clock at 805e9984 #7 [8de7fa70] poll_schedule_timeout at 8018e8f8 #8 [8de7fa88] do_select at 8018f338 #9 [8de7fd88] core_sys_select at 8018f5cc #10 [8de7fee0] sys_select at 8018f854 #11 [8de7ff28] syscall_common at 80028fc8 The lock seems to be there to protect the hardware counters so there is no need to hold it across irq_work_run(). Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The locking order of vlan_rwsem (LOCK A) and then rtnl (LOCK B), contradicts other flows such as ipoib_open possibly causing a deadlock. To prevent this deadlock heavy flush is called with RTNL locked and only then tries to acquire vlan_rwsem. This deadlock is possible only when there are child interfaces. [ 140.941758] ====================================================== [ 140.946276] WARNING: possible circular locking dependency detected [ 140.950950] 4.15.0-rc1+ #9 Tainted: G O [ 140.954797] ------------------------------------------------------ [ 140.959424] kworker/u32:1/146 is trying to acquire lock: [ 140.963450] (rtnl_mutex){+.+.}, at: [<ffffffffc083516a>] __ipoib_ib_dev_flush+0x2da/0x4e0 [ib_ipoib] [ 140.970006] but task is already holding lock: [ 140.975141] (&priv->vlan_rwsem){++++}, at: [<ffffffffc0834ee1>] __ipoib_ib_dev_flush+0x51/0x4e0 [ib_ipoib] [ 140.982105] which lock already depends on the new lock. [ 140.990023] the existing dependency chain (in reverse order) is: [ 140.998650] -> #1 (&priv->vlan_rwsem){++++}: [ 141.005276] down_read+0x4d/0xb0 [ 141.009560] ipoib_open+0xad/0x120 [ib_ipoib] [ 141.014400] __dev_open+0xcb/0x140 [ 141.017919] __dev_change_flags+0x1a4/0x1e0 [ 141.022133] dev_change_flags+0x23/0x60 [ 141.025695] devinet_ioctl+0x704/0x7d0 [ 141.029156] sock_do_ioctl+0x20/0x50 [ 141.032526] sock_ioctl+0x221/0x300 [ 141.036079] do_vfs_ioctl+0xa6/0x6d0 [ 141.039656] SyS_ioctl+0x74/0x80 [ 141.042811] entry_SYSCALL_64_fastpath+0x1f/0x96 [ 141.046891] -> #0 (rtnl_mutex){+.+.}: [ 141.051701] lock_acquire+0xd4/0x220 [ 141.055212] __mutex_lock+0x88/0x970 [ 141.058631] __ipoib_ib_dev_flush+0x2da/0x4e0 [ib_ipoib] [ 141.063160] __ipoib_ib_dev_flush+0x71/0x4e0 [ib_ipoib] [ 141.067648] process_one_work+0x1f5/0x610 [ 141.071429] worker_thread+0x4a/0x3f0 [ 141.074890] kthread+0x141/0x180 [ 141.078085] ret_from_fork+0x24/0x30 [ 141.081559] other info that might help us debug this: [ 141.088967] Possible unsafe locking scenario: [ 141.094280] CPU0 CPU1 [ 141.097953] ---- ---- [ 141.101640] lock(&priv->vlan_rwsem); [ 141.104771] lock(rtnl_mutex); [ 141.109207] lock(&priv->vlan_rwsem); [ 141.114032] lock(rtnl_mutex); [ 141.116800] *** DEADLOCK *** Fixes: b4b678b ("IB/ipoib: Grab rtnl lock on heavy flush when calling ndo_open/stop") Signed-off-by: Alex Vesker <valex@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
A prototype patchset posted to the list for discussion: (@pcmoore You can assign this to me if you want :) |
Deferred struct page init is needed only on systems with large amount of physical memory to improve boot performance. 32-bit systems do not benefit from this feature. Jiri reported a problem where deferred struct pages do not work well with x86-32: [ 0.035162] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) [ 0.035725] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) [ 0.036269] Initializing CPU#0 [ 0.036513] Initializing HighMem for node 0 (00036ffe:0007ffe0) [ 0.038459] page:f6780000 is uninitialized and poisoned [ 0.038460] raw: ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff [ 0.039509] page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page)) [ 0.040038] ------------[ cut here ]------------ [ 0.040399] kernel BUG at include/linux/page-flags.h:293! [ 0.040823] invalid opcode: 0000 [#1] SMP PTI [ 0.041166] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc1_pt_jiri #9 [ 0.041694] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 [ 0.042496] EIP: free_highmem_page+0x64/0x80 [ 0.042839] Code: 13 46 d8 c1 e8 18 5d 83 e0 03 8d 04 c0 c1 e0 06 ff 80 ec 5f 44 d8 c3 8d b4 26 00 00 00 00 ba 08 65 28 d8 89 d8 e8 fc 71 02 00 <0f> 0b 8d 76 00 8d bc 27 00 00 00 00 ba d0 b1 26 d8 89 d8 e8 e4 71 [ 0.044338] EAX: 0000003c EBX: f6780000 ECX: 00000000 EDX: d856cbe8 [ 0.044868] ESI: 0007ffe0 EDI: d838df20 EBP: d838df00 ESP: d838defc [ 0.045372] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210086 [ 0.045913] CR0: 80050033 CR2: 00000000 CR3: 18556000 CR4: 00040690 [ 0.046413] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 0.046913] DR6: fffe0ff0 DR7: 00000400 [ 0.047220] Call Trace: [ 0.047419] add_highpages_with_active_regions+0xbd/0x10d [ 0.047854] set_highmem_pages_init+0x5b/0x71 [ 0.048202] mem_init+0x2b/0x1e8 [ 0.048460] start_kernel+0x1d2/0x425 [ 0.048757] i386_start_kernel+0x93/0x97 [ 0.049073] startup_32_smp+0x164/0x168 [ 0.049379] Modules linked in: [ 0.049626] ---[ end trace 337949378db0abbb ]--- We free highmem pages before their struct pages are initialized: mem_init() set_highmem_pages_init() add_highpages_with_active_regions() free_highmem_page() .. Access uninitialized struct page here.. Because there is no reason to have this feature on 32-bit systems, just disable it. Link: http://lkml.kernel.org/r/20180831150506.31246-1-pavel.tatashin@microsoft.com Fixes: 2e3ca40 ("mm: relax deferred struct page requirements") Signed-off-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reported-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Defer probe of qman portals after qman probing. This fixes the crash below, seen on NXP LS1043A SoCs: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 Mem abort info: ESR = 0x96000004 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [0000000000000004] user address but active_mm is swapper Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc1-next-20180622-00200-g986f5c179185 #9 Hardware name: LS1043A RDB Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO) pc : qman_set_sdest+0x74/0xa0 lr : qman_portal_probe+0x22c/0x470 sp : ffff00000803bbc0 x29: ffff00000803bbc0 x28: 0000000000000000 x27: ffff0000090c1b88 x26: ffff00000927cb68 x25: ffff00000927c000 x24: ffff00000927cb60 x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000090e9000 x20: ffff800073b5c810 x19: ffff800027401298 x18: ffffffffffffffff x17: 0000000000000001 x16: 0000000000000000 x15: ffff0000090e96c8 x14: ffff80002740138a x13: ffff0000090f2000 x12: 0000000000000030 x11: ffff000008f25000 x10: 0000000000000000 x9 : ffff80007bdfd2c0 x8 : 0000000000004000 x7 : ffff80007393cc18 x6 : 0040000000000001 x5 : 0000000000000000 x4 : ffffffffffffffff x3 : 0000000000000004 x2 : ffff00000927c900 x1 : 0000000000000000 x0 : 0000000000000004 Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____)) Call trace: qman_set_sdest+0x74/0xa0 platform_drv_probe+0x50/0xa8 driver_probe_device+0x214/0x2f8 __driver_attach+0xd8/0xe0 bus_for_each_dev+0x68/0xc8 driver_attach+0x20/0x28 bus_add_driver+0x108/0x228 driver_register+0x60/0x110 __platform_driver_register+0x40/0x48 qman_portal_driver_init+0x20/0x84 do_one_initcall+0x58/0x168 kernel_init_freeable+0x184/0x22c kernel_init+0x10/0x108 ret_from_fork+0x10/0x18 Code: f9400443 11001000 927e4800 8b000063 (b9400063) ---[ end trace 4f6d50489ecfb930 ]--- Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Signed-off-by: Li Yang <leoyang.li@nxp.com>
@WOnder93 , I want to try this patch, this also need auditd change, right ? any patches for it ? |
@michael-skynorth That patchset only partially solves the problem. It adds records with some information that you can use to reconstruct the full path, but you'd have to do that manually. Basically, you'd need to look at the values of the fd arguments in the SYSCALL record, translate those to paths based on the FD_PATH records and then append the corresponding relative paths from the PATH records. You'd also need to watch out for the corner case from issue #95 (but that's easy to detect). After discussing the patchset we came to conclusion that this issue would be better resolved in a different way - ideally by providing full correct path in the PATH records. That solution doesn't need any changes in audit userspace, but will be a bit more difficult to implement. Currently there is an ongoing discussion about how exactly we want to solve the problem (see the thread related to issue #95 [1]-[5]) so it is unlikely we will have a solution before we come to an agreement on that. [1] https://www.redhat.com/archives/linux-audit/2018-August/msg00003.html |
@WOnder93 , thanks so much for the detailed response. |
Revert the commit bd293d0. The proper fix has been made available with commit d0a255e ("loop: set PF_MEMALLOC_NOIO for the worker thread"). Note that the fix offered by commit bd293d0 doesn't really prevent the deadlock from occuring - if we look at the stacktrace reported by Junxiao Bi, we see that it hangs in bit_wait_io and not on the mutex - i.e. it has already successfully taken the mutex. Changing the mutex from mutex_lock to mutex_trylock won't help with deadlocks that happen afterwards. PID: 474 TASK: ffff8813e11f4600 CPU: 10 COMMAND: "kswapd0" #0 [ffff8813dedfb938] __schedule at ffffffff8173f405 #1 [ffff8813dedfb990] schedule at ffffffff8173fa27 #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186 #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8 #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81 #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio] #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio] #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio] #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778 #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f #13 [ffff8813dedfbec0] kthread at ffffffff810a8428 #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Fixes: bd293d0 ("dm bufio: fix deadlock with loop device") Depends-on: d0a255e ("loop: set PF_MEMALLOC_NOIO for the worker thread") Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Hayes Wang says: ==================== r8152: serial fixes v3: 1. Fix the typos for patch #5 and #6. 2. Modify the commit message of patch #9. v2: For patch #2, move declaring the variable "ocp_data". v1: These patches are used to fix some issues for RTL8153. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Fix tcon use-after-free and NULL ptr deref. Customer system crashes with the following kernel log: [462233.169868] CIFS VFS: Cancelling wait for mid 4894753 cmd: 14 => a QUERY DIR [462233.228045] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4 [462233.305922] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4 [462233.306205] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4 [462233.347060] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4 [462233.347107] CIFS VFS: Close unmatched open [462233.347113] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 ... [exception RIP: cifs_put_tcon+0xa0] (this is doing tcon->ses->server) #6 [...] smb2_cancelled_close_fid at ... [cifs] #7 [...] process_one_work at ... #8 [...] worker_thread at ... #9 [...] kthread at ... The most likely explanation we have is: * When we put the last reference of a tcon (refcount=0), we close the cached share root handle. * If closing a handle is interrupted, SMB2_close() will queue a SMB2_close() in a work thread. * The queued object keeps a tcon ref so we bump the tcon refcount, jumping from 0 to 1. * We reach the end of cifs_put_tcon(), we free the tcon object despite it now having a refcount of 1. * The queued work now runs, but the tcon, ses & server was freed in the meantime resulting in a crash. THREAD 1 ======== cifs_put_tcon => tcon refcount reach 0 SMB2_tdis close_shroot_lease close_shroot_lease_locked => if cached root has lease && refcount = 0 smb2_close_cached_fid => if cached root valid SMB2_close => retry close in a thread if interrupted smb2_handle_cancelled_close __smb2_handle_cancelled_close => !! tcon refcount bump 0 => 1 !! INIT_WORK(&cancelled->work, smb2_cancelled_close_fid); queue_work(cifsiod_wq, &cancelled->work) => queue work tconInfoFree(tcon); ==> freed! cifs_put_smb_ses(ses); ==> freed! THREAD 2 (workqueue) ======== smb2_cancelled_close_fid SMB2_close(0, cancelled->tcon, ...); => use-after-free of tcon cifs_put_tcon(cancelled->tcon); => tcon refcount reach 0 second time *CRASH* Fixes: d919131 ("CIFS: Close cached root handle only if it has a lease") Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
This BUG halt was reported a while back, but the patch somehow got missed: PID: 2879 TASK: c16adaa0 CPU: 1 COMMAND: "sctpn" #0 [f418dd28] crash_kexec at c04a7d8c #1 [f418dd7c] oops_end at c0863e02 #2 [f418dd90] do_invalid_op at c040aaca #3 [f418de28] error_code (via invalid_op) at c08631a5 EAX: f34baac0 EBX: 00000090 ECX: f418deb0 EDX: f5542950 EBP: 00000000 DS: 007b ESI: f34ba800 ES: 007b EDI: f418dea0 GS: 00e0 CS: 0060 EIP: c046fa5e ERR: ffffffff EFLAGS: 00010286 #4 [f418de5c] add_timer at c046fa5e #5 [f418de68] sctp_do_sm at f8db8c77 [sctp] #6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp] #7 [f418df48] inet_shutdown at c080baf9 #8 [f418df5c] sys_shutdown at c079eedf #9 [f418df70] sys_socketcall at c079fe88 EAX: ffffffda EBX: 0000000d ECX: bfceea90 EDX: 0937af98 DS: 007b ESI: 0000000c ES: 007b EDI: b7150ae4 SS: 007b ESP: bfceea7c EBP: bfceeaa8 GS: 0033 CS: 0073 EIP: b775c424 ERR: 00000066 EFLAGS: 00000282 It appears that the side effect that starts the shutdown timer was processed multiple times, which can happen as multiple paths can trigger it. This of course leads to the BUG halt in add_timer getting called. Fix seems pretty straightforward, just check before the timer is added if its already been started. If it has mod the timer instead to min(current expiration, new expiration) Its been tested but not confirmed to fix the problem, as the issue has only occured in production environments where test kernels are enjoined from being installed. It appears to be a sane fix to me though. Also, recentely, Jere found a reproducer posted on list to confirm that this resolves the issues Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Vlad Yasevich <vyasevich@gmail.com> CC: "David S. Miller" <davem@davemloft.net> CC: jere.leppanen@nokia.com CC: marcelo.leitner@gmail.com CC: netdev@vger.kernel.org Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
If the key is already present then free the key used for lookup. Found with: $ perf stat -M IO_Read_BW /bin/true ==1749112==ERROR: LeakSanitizer: detected memory leaks Direct leak of 32 byte(s) in 4 object(s) allocated from: #0 0x7f6f6fa7d7cf in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145 #1 0x55acecd9d7a6 in check_per_pkg util/stat.c:343 #2 0x55acecd9d9c5 in process_counter_values util/stat.c:365 #3 0x55acecd9e0ab in process_counter_maps util/stat.c:421 #4 0x55acecd9e292 in perf_stat_process_counter util/stat.c:443 #5 0x55aceca8553e in read_counters ./tools/perf/builtin-stat.c:470 #6 0x55aceca88fe3 in __run_perf_stat ./tools/perf/builtin-stat.c:1023 #7 0x55aceca89146 in run_perf_stat ./tools/perf/builtin-stat.c:1048 #8 0x55aceca90858 in cmd_stat ./tools/perf/builtin-stat.c:2555 #9 0x55acecc05fa5 in run_builtin ./tools/perf/perf.c:313 #10 0x55acecc064fe in handle_internal_command ./tools/perf/perf.c:365 #11 0x55acecc068bb in run_argv ./tools/perf/perf.c:409 #12 0x55acecc070aa in main ./tools/perf/perf.c:539 Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Garry <john.garry@huawei.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Clarke <pc@us.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Stephane Eranian <eranian@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Vineet Singh <vineet.singh@intel.com> Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: zhengjun.xing@intel.com Link: https://lore.kernel.org/r/20220105061351.120843-24-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Patch series "mm: COW fixes part 1: fix the COW security issue for THP and swap", v3. This series attempts to optimize and streamline the COW logic for ordinary anon pages and THP anon pages, fixing two remaining instances of CVE-2020-29374 in do_swap_page() and do_huge_pmd_wp_page(): information can leak from a parent process to a child process via anonymous pages shared during fork(). This issue, including other related COW issues, has been summarized in [2]: "1. Observing Memory Modifications of Private Pages From A Child Process Long story short: process-private memory might not be as private as you think once you fork(): successive modifications of private memory regions in the parent process can still be observed by the child process, for example, by smart use of vmsplice()+munmap(). The core problem is that pinning pages readable in a child process, such as done via the vmsplice system call, can result in a child process observing memory modifications done in the parent process the child is not supposed to observe. [1] contains an excellent summary and [2] contains further details. This issue was assigned CVE-2020-29374 [9]. For this to trigger, it's required to use a fork() without subsequent exec(), for example, as used under Android zygote. Without further details about an application that forks less-privileged child processes, one cannot really say what's actually affected and what's not -- see the details section the end of this mail for a short sshd/openssh analysis. While commit 1783985 ("gup: document and work around "COW can break either way" issue") fixed this issue and resulted in other problems (e.g., ptrace on pmem), commit 09854ba ("mm: do_wp_page() simplification") re-introduced part of the problem unfortunately. The original reproducer can be modified quite easily to use THP [3] and make the issue appear again on upstream kernels. I modified it to use hugetlb [4] and it triggers as well. The problem is certainly less severe with hugetlb than with THP; it merely highlights that we still have plenty of open holes we should be closing/fixing. Regarding vmsplice(), the only known workaround is to disallow the vmsplice() system call ... or disable THP and hugetlb. But who knows what else is affected (RDMA? O_DIRECT?) to achieve the same goal -- in the end, it's a more generic issue" This security issue was first reported by Jann Horn on 27 May 2020 and it currently affects anonymous pages during swapin, anonymous THP and hugetlb. This series tackles anonymous pages during swapin and anonymous THP: - do_swap_page() for handling COW on PTEs during swapin directly - do_huge_pmd_wp_page() for handling COW on PMD-mapped THP during write faults With this series, we'll apply the same COW logic we have in do_wp_page() to all swappable anon pages: don't reuse (map writable) the page in case there are additional references (page_count() != 1). All users of reuse_swap_page() are remove, and consequently reuse_swap_page() is removed. In general, we're struggling with the following COW-related issues: (1) "missed COW": we miss to copy on write and reuse the page (map it writable) although we must copy because there are pending references from another process to this page. The result is a security issue. (2) "wrong COW": we copy on write although we wouldn't have to and shouldn't: if there are valid GUP references, they will become out of sync with the pages mapped into the page table. We fail to detect that such a page can be reused safely, especially if never more than a single process mapped the page. The result is an intra process memory corruption. (3) "unnecessary COW": we copy on write although we wouldn't have to: performance degradation and temporary increases swap+memory consumption can be the result. While this series fixes (1) for swappable anon pages, it tries to reduce reported cases of (3) first as good and easy as possible to limit the impact when streamlining. The individual patches try to describe in which cases we will run into (3). This series certainly makes (2) worse for THP, because a THP will now get PTE-mapped on write faults if there are additional references, even if there was only ever a single process involved: once PTE-mapped, we'll copy each and every subpage and won't reuse any subpage as long as the underlying compound page wasn't split. I'm working on an approach to fix (2) and improve (3): PageAnonExclusive to mark anon pages that are exclusive to a single process, allow GUP pins only on such exclusive pages, and allow turning exclusive pages shared (clearing PageAnonExclusive) only if there are no GUP pins. Anon pages with PageAnonExclusive set never have to be copied during write faults, but eventually during fork() if they cannot be turned shared. The improved reuse logic in this series will essentially also be the logic to reset PageAnonExclusive. This work will certainly take a while, but I'm planning on sharing details before having code fully ready. #1-#5 can be applied independently of the rest. #6-#9 are mostly only cleanups related to reuse_swap_page(). Notes: * For now, I'll leave hugetlb code untouched: "unnecessary COW" might easily break existing setups because hugetlb pages are a scarce resource and we could just end up having to crash the application when we run out of hugetlb pages. We have to be very careful and the security aspect with hugetlb is most certainly less relevant than for unprivileged anon pages. * Instead of lru_add_drain() we might actually just drain the lru_add list or even just remove the single page of interest from the lru_add list. This would require a new helper function, and could be added if the conditional lru_add_drain() turn out to be a problem. * I extended the test case already included in [1] to also test for the newly found do_swap_page() case. I'll send that out separately once/if this part was merged. [1] https://lkml.kernel.org/r/20211217113049.23850-1-david@redhat.com [2] https://lore.kernel.org/r/3ae33b08-d9ef-f846-56fb-645e3b9b4c66@redhat.com This patch (of 9): Liang Zhang reported [1] that the current COW logic in do_wp_page() is sub-optimal when it comes to swap+read fault+write fault of anonymous pages that have a single user, visible via a performance degradation in the redis benchmark. Something similar was previously reported [2] by Nadav with a simple reproducer. After we put an anon page into the swapcache and unmapped it from a single process, that process might read that page again and refault it read-only. If that process then writes to that page, the process is actually the exclusive user of the page, however, the COW logic in do_co_page() won't be able to reuse it due to the additional reference from the swapcache. Let's optimize for pages that have been added to the swapcache but only have an exclusive user. Try removing the swapcache reference if there is hope that we're the exclusive user. We will fail removing the swapcache reference in two scenarios: (1) There are additional swap entries referencing the page: copying instead of reusing is the right thing to do. (2) The page is under writeback: theoretically we might be able to reuse in some cases, however, we cannot remove the additional reference and will have to copy. Note that we'll only try removing the page from the swapcache when it's highly likely that we'll be the exclusive owner after removing the page from the swapache. As we're about to map that page writable and redirty it, that should not affect reclaim but is rather the right thing to do. Further, we might have additional references from the LRU pagevecs, which will force us to copy instead of being able to reuse. We'll try handling such references for some scenarios next. Concurrent writeback cannot be handled easily and we'll always have to copy. While at it, remove the superfluous page_mapcount() check: it's implicitly covered by the page_count() for ordinary anon pages. [1] https://lkml.kernel.org/r/20220113140318.11117-1-zhangliang5@huawei.com [2] https://lkml.kernel.org/r/0480D692-D9B2-429A-9A88-9BBA1331AC3A@gmail.com Link: https://lkml.kernel.org/r/20220131162940.210846-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Liang Zhang <zhangliang5@huawei.com> Reported-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Jann Horn <jannh@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Don Dutile <ddutile@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As guest_irq is coming from KVM_IRQFD API call, it may trigger crash in svm_update_pi_irte() due to out-of-bounds: crash> bt PID: 22218 TASK: ffff951a6ad74980 CPU: 73 COMMAND: "vcpu8" #0 [ffffb1ba6707fa40] machine_kexec at ffffffff8565b397 #1 [ffffb1ba6707fa90] __crash_kexec at ffffffff85788a6d #2 [ffffb1ba6707fb58] crash_kexec at ffffffff8578995d #3 [ffffb1ba6707fb70] oops_end at ffffffff85623c0d #4 [ffffb1ba6707fb90] no_context at ffffffff856692c9 #5 [ffffb1ba6707fbf8] exc_page_fault at ffffffff85f95b51 #6 [ffffb1ba6707fc50] asm_exc_page_fault at ffffffff86000ace [exception RIP: svm_update_pi_irte+227] RIP: ffffffffc0761b53 RSP: ffffb1ba6707fd08 RFLAGS: 00010086 RAX: ffffb1ba6707fd78 RBX: ffffb1ba66d91000 RCX: 0000000000000001 RDX: 00003c803f63f1c0 RSI: 000000000000019a RDI: ffffb1ba66db2ab8 RBP: 000000000000019a R8: 0000000000000040 R9: ffff94ca41b82200 R10: ffffffffffffffcf R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000001 R14: ffffffffffffffcf R15: 000000000000005f ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffb1ba6707fdb8] kvm_irq_routing_update at ffffffffc09f19a1 [kvm] #8 [ffffb1ba6707fde0] kvm_set_irq_routing at ffffffffc09f2133 [kvm] #9 [ffffb1ba6707fe18] kvm_vm_ioctl at ffffffffc09ef544 [kvm] RIP: 00007f143c36488b RSP: 00007f143a4e04b8 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 00007f05780041d0 RCX: 00007f143c36488b RDX: 00007f05780041d0 RSI: 000000004008ae6a RDI: 0000000000000020 RBP: 00000000000004e8 R8: 0000000000000008 R9: 00007f05780041e0 R10: 00007f0578004560 R11: 0000000000000246 R12: 00000000000004e0 R13: 000000000000001a R14: 00007f1424001c60 R15: 00007f0578003bc0 ORIG_RAX: 0000000000000010 CS: 0033 SS: 002b Vmx have been fix this in commit 3a8b067 (KVM: VMX: Do not BUG() on out-of-bounds guest IRQ), so we can just copy source from that to fix this. Co-developed-by: Yi Liu <liu.yi24@zte.com.cn> Signed-off-by: Yi Liu <liu.yi24@zte.com.cn> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Message-Id: <20220309113025.44469-1-wang.yi59@zte.com.cn> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While handling PCI errors (AER flow) driver tries to disable NAPI [napi_disable()] after NAPI is deleted [__netif_napi_del()] which causes unexpected system hang/crash. System message log shows the following: ======================================= [ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures. [ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)' [ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->error_detected(IO frozen) [ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports: 'need reset' [ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking bnx2x->error_detected(IO frozen) [ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports: 'need reset' [ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset' [ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow: [ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows: [ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow: [ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows: [ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset' [ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking bnx2x->slot_reset() [ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing... [ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset --> driver unload Uninterruptible tasks ===================== crash> ps | grep UN 213 2 11 c000000004c89e00 UN 0.0 0 0 [eehd] 215 2 0 c000000004c80000 UN 0.0 0 0 [kworker/0:2] 2196 1 28 c000000004504f00 UN 0.1 15936 11136 wickedd 4287 1 9 c00000020d076800 UN 0.0 4032 3008 agetty 4289 1 20 c00000020d056680 UN 0.0 7232 3840 agetty 32423 2 26 c00000020038c580 UN 0.0 0 0 [kworker/26:3] 32871 4241 27 c0000002609ddd00 UN 0.1 18624 11648 sshd 32920 10130 16 c00000027284a100 UN 0.1 48512 12608 sendmail 33092 32987 0 c000000205218b00 UN 0.1 48512 12608 sendmail 33154 4567 16 c000000260e51780 UN 0.1 48832 12864 pickup 33209 4241 36 c000000270cb6500 UN 0.1 18624 11712 sshd 33473 33283 0 c000000205211480 UN 0.1 48512 12672 sendmail 33531 4241 37 c00000023c902780 UN 0.1 18624 11648 sshd EEH handler hung while bnx2x sleeping and holding RTNL lock =========================================================== crash> bt 213 PID: 213 TASK: c000000004c89e00 CPU: 11 COMMAND: "eehd" #0 [c000000004d477e0] __schedule at c000000000c70808 #1 [c000000004d478b0] schedule at c000000000c70ee0 #2 [c000000004d478e0] schedule_timeout at c000000000c76dec #3 [c000000004d479c0] msleep at c0000000002120cc #4 [c000000004d479f0] napi_disable at c000000000a06448 ^^^^^^^^^^^^^^^^ #5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x] #6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x] #7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc #8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8 #9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64 And the sleeping source code ============================ crash> dis -ls c000000000a06448 FILE: ../net/core/dev.c LINE: 6702 6697 { 6698 might_sleep(); 6699 set_bit(NAPI_STATE_DISABLE, &n->state); 6700 6701 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state)) * 6702 msleep(1); 6703 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state)) 6704 msleep(1); 6705 6706 hrtimer_cancel(&n->timer); 6707 6708 clear_bit(NAPI_STATE_DISABLE, &n->state); 6709 } EEH calls into bnx2x twice based on the system log above, first through bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes the following call chains: bnx2x_io_error_detected() +-> bnx2x_eeh_nic_unload() +-> bnx2x_del_all_napi() +-> __netif_napi_del() bnx2x_io_slot_reset() +-> bnx2x_netif_stop() +-> bnx2x_napi_disable() +->napi_disable() Fix this by correcting the sequence of NAPI APIs usage, that is delete the NAPI after disabling it. Fixes: 7fa6f34 ("bnx2x: AER revised") Reported-by: David Christensen <drc@linux.vnet.ibm.com> Tested-by: David Christensen <drc@linux.vnet.ibm.com> Signed-off-by: Manish Chopra <manishc@marvell.com> Signed-off-by: Ariel Elior <aelior@marvell.com> Link: https://lore.kernel.org/r/20220426153913.6966-1-manishc@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This fixes the following error caused by a race condition between phydev->adjust_link() and a MDIO transaction in the phy interrupt handler. The issue was reproduced with the ethernet FEC driver and a micrel KSZ9031 phy. [ 146.195696] fec 2188000.ethernet eth0: MDIO read timeout [ 146.201779] ------------[ cut here ]------------ [ 146.206671] WARNING: CPU: 0 PID: 571 at drivers/net/phy/phy.c:942 phy_error+0x24/0x6c [ 146.214744] Modules linked in: bnep imx_vdoa imx_sdma evbug [ 146.220640] CPU: 0 PID: 571 Comm: irq/128-2188000 Not tainted 5.18.0-rc3-00080-gd569e86915b7 #9 [ 146.229563] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [ 146.236257] unwind_backtrace from show_stack+0x10/0x14 [ 146.241640] show_stack from dump_stack_lvl+0x58/0x70 [ 146.246841] dump_stack_lvl from __warn+0xb4/0x24c [ 146.251772] __warn from warn_slowpath_fmt+0x5c/0xd4 [ 146.256873] warn_slowpath_fmt from phy_error+0x24/0x6c [ 146.262249] phy_error from kszphy_handle_interrupt+0x40/0x48 [ 146.268159] kszphy_handle_interrupt from irq_thread_fn+0x1c/0x78 [ 146.274417] irq_thread_fn from irq_thread+0xf0/0x1dc [ 146.279605] irq_thread from kthread+0xe4/0x104 [ 146.284267] kthread from ret_from_fork+0x14/0x28 [ 146.289164] Exception stack(0xe6fa1fb0 to 0xe6fa1ff8) [ 146.294448] 1fa0: 00000000 00000000 00000000 00000000 [ 146.302842] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 146.311281] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 146.318262] irq event stamp: 12325 [ 146.321780] hardirqs last enabled at (12333): [<c01984c4>] __up_console_sem+0x50/0x60 [ 146.330013] hardirqs last disabled at (12342): [<c01984b0>] __up_console_sem+0x3c/0x60 [ 146.338259] softirqs last enabled at (12324): [<c01017f0>] __do_softirq+0x2c0/0x624 [ 146.346311] softirqs last disabled at (12319): [<c01300ac>] __irq_exit_rcu+0x138/0x178 [ 146.354447] ---[ end trace 0000000000000000 ]--- With the FEC driver phydev->adjust_link() calls fec_enet_adjust_link() calls fec_stop()/fec_restart() and both these function reset and temporary disable the FEC disrupting any MII transaction that could be happening at the same time. fec_enet_adjust_link() and phy_read() can be running at the same time when we have one additional interrupt before the phy_state_machine() is able to terminate. Thread 1 (phylib WQ) | Thread 2 (phy interrupt) | | phy_interrupt() <-- PHY IRQ | handle_interrupt() | phy_read() | phy_trigger_machine() | --> schedule phylib WQ | | phy_state_machine() | phy_check_link_status() | phy_link_change() | phydev->adjust_link() | fec_enet_adjust_link() | --> FEC reset | phy_interrupt() <-- PHY IRQ | phy_read() | Fix this by acquiring the phydev lock in phy_interrupt(). Link: https://lore.kernel.org/all/20220422152612.GA510015@francesco-nb.int.toradex.com/ Fixes: c974bdb ("net: phy: Use threaded IRQ, to allow IRQ from sleeping devices") cc: <stable@vger.kernel.org> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20220506060815.327382-1-francesco.dolcini@toradex.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Do not allow to write timestamps on RX rings if PF is being configured. When PF is being configured RX rings can be freed or rebuilt. If at the same time timestamps are updated, the kernel will crash by dereferencing null RX ring pointer. PID: 1449 TASK: ff187d28ed658040 CPU: 34 COMMAND: "ice-ptp-0000:51" #0 [ff1966a94a713bb0] machine_kexec at ffffffff9d05a0be #1 [ff1966a94a713c08] __crash_kexec at ffffffff9d192e9d #2 [ff1966a94a713cd0] crash_kexec at ffffffff9d1941bd #3 [ff1966a94a713ce8] oops_end at ffffffff9d01bd54 #4 [ff1966a94a713d08] no_context at ffffffff9d06bda4 #5 [ff1966a94a713d60] __bad_area_nosemaphore at ffffffff9d06c10c #6 [ff1966a94a713da8] do_page_fault at ffffffff9d06cae4 #7 [ff1966a94a713de0] page_fault at ffffffff9da0107e [exception RIP: ice_ptp_update_cached_phctime+91] RIP: ffffffffc076db8b RSP: ff1966a94a713e98 RFLAGS: 00010246 RAX: 16e3db9c6b7ccae4 RBX: ff187d269dd3c180 RCX: ff187d269cd4d018 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ff187d269cfcc644 R8: ff187d339b9641b0 R9: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: ff187d269cfcc648 R13: ffffffff9f128784 R14: ffffffff9d101b70 R15: ff187d269cfcc640 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ff1966a94a713ea0] ice_ptp_periodic_work at ffffffffc076dbef [ice] #9 [ff1966a94a713ee0] kthread_worker_fn at ffffffff9d101c1b #10 [ff1966a94a713f10] kthread at ffffffff9d101b4d #11 [ff1966a94a713f50] ret_from_fork at ffffffff9da0023f Fixes: 77a7811 ("ice: enable receive hardware timestamping") Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com> Reviewed-by: Michal Schmidt <mschmidt@redhat.com> Tested-by: Dave Cain <dcain@redhat.com> Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Ido Schimmel says: ==================== bridge: mcast: Extensions for EVPN tl;dr ===== This patchset creates feature parity between user space and the kernel and allows the former to install and replace MDB port group entries with a source list and associated filter mode. This is required for EVPN use cases where multicast state is not derived from snooped IGMP/MLD packets, but instead derived from EVPN routes exchanged by the control plane in user space. Background ========== IGMPv3 [1] and MLDv2 [2] differ from earlier versions of the protocols in that they add support for source-specific multicast. That is, hosts can advertise interest in listening to a particular multicast address only from specific source addresses or from all sources except for specific source addresses. In kernel 5.10 [3][4], the bridge driver gained the ability to snoop IGMPv3/MLDv2 packets and install corresponding MDB port group entries. For example, a snooped IGMPv3 Membership Report that contains a single MODE_IS_EXCLUDE record for group 239.10.10.10 with sources 192.0.2.1, 192.0.2.2, 192.0.2.20 and 192.0.2.21 would trigger the creation of these entries: # bridge -d mdb show dev br0 port veth1 grp 239.10.10.10 src 192.0.2.21 temp filter_mode include proto kernel blocked dev br0 port veth1 grp 239.10.10.10 src 192.0.2.20 temp filter_mode include proto kernel blocked dev br0 port veth1 grp 239.10.10.10 src 192.0.2.2 temp filter_mode include proto kernel blocked dev br0 port veth1 grp 239.10.10.10 src 192.0.2.1 temp filter_mode include proto kernel blocked dev br0 port veth1 grp 239.10.10.10 temp filter_mode exclude source_list 192.0.2.21/0.00,192.0.2.20/0.00,192.0.2.2/0.00,192.0.2.1/0.00 proto kernel While the kernel can install and replace entries with a filter mode and source list, user space cannot. It can only add EXCLUDE entries with an empty source list, which is sufficient for IGMPv2/MLDv1, but not for IGMPv3/MLDv2. Use cases where the multicast state is not derived from snooped packets, but instead derived from routes exchanged by the user space control plane require feature parity between user space and the kernel in terms of MDB configuration. Such a use case is detailed in the next section. Motivation ========== RFC 7432 [5] defines a "MAC/IP Advertisement route" (type 2) [6] that allows NVE switches in the EVPN network to advertise and learn reachability information for unicast MAC addresses. Traffic destined to a unicast MAC address can therefore be selectively forwarded to a single NVE switch behind which the MAC is located. The same is not true for IP multicast traffic. Such traffic is simply flooded as BUM to all NVE switches in the broadcast domain (BD), regardless if a switch has interested receivers for the multicast stream or not. This is especially problematic for overlay networks that make heavy use of multicast. The issue is addressed by RFC 9251 [7] that defines a "Selective Multicast Ethernet Tag Route" (type 6) [8] which allows NVE switches in the EVPN network to advertise multicast streams that they are interested in. This is done by having each switch suppress IGMP/MLD packets from being transmitted to the NVE network and instead communicate the information over BGP to other switches. As far as the bridge driver is concerned, the above means that the multicast state (i.e., {multicast address, group timer, filter-mode, (source records)}) for the VXLAN bridge port is not populated by the kernel from snooped IGMP/MLD packets (they are suppressed), but instead by user space. Specifically, by the routing daemon that is exchanging EVPN routes with other NVE switches. Changes are obviously also required in the VXLAN driver, but they are the subject of future patchsets. See the "Future work" section. Implementation ============== The user interface is extended to allow user space to specify the filter mode of the MDB port group entry and its source list. Replace support is also added so that user space would not need to remove an entry and re-add it only to edit its source list or filter mode, as that would result in packet loss. Example usage: # bridge mdb replace dev br0 port dummy10 grp 239.1.1.1 permanent \ source_list 192.0.2.1,192.0.2.3 filter_mode exclude proto zebra # bridge -d -s mdb show dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.3 permanent filter_mode include proto zebra blocked 0.00 dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent filter_mode include proto zebra blocked 0.00 dev br0 port dummy10 grp 239.1.1.1 permanent filter_mode exclude source_list 192.0.2.3/0.00,192.0.2.1/0.00 proto zebra 0.00 The netlink interface is extended with a few new attributes in the RTM_NEWMDB request message: [ struct nlmsghdr ] [ struct br_port_msg ] [ MDBA_SET_ENTRY ] struct br_mdb_entry [ MDBA_SET_ENTRY_ATTRS ] [ MDBE_ATTR_SOURCE ] struct in_addr / struct in6_addr [ MDBE_ATTR_SRC_LIST ] // new [ MDBE_SRC_LIST_ENTRY ] [ MDBE_SRCATTR_ADDRESS ] struct in_addr / struct in6_addr [ ...] [ MDBE_ATTR_GROUP_MODE ] // new u8 [ MDBE_ATTR_RTPORT ] // new u8 No changes are required in RTM_NEWMDB responses and notifications, as all the information can already be dumped by the kernel today. Testing ======= Tested with existing bridge multicast selftests: bridge_igmp.sh, bridge_mdb_port_down.sh, bridge_mdb.sh, bridge_mld.sh, bridge_vlan_mcast.sh. In addition, added many new test cases for existing as well as for new MDB functionality. Patchset overview ================= Patches #1-#8 are non-functional preparations for the core changes in later patches. Patches #9-#10 allow user space to install (*, G) entries with a source list and associated filter mode. Specifically, patch #9 adds the necessary kernel plumbing and patch #10 exposes the new functionality to user space via a few new attributes. Patch #11 allows user space to specify the routing protocol of new MDB port group entries so that a routing daemon could differentiate between entries installed by it and those installed by an administrator. Patch #12 allows user space to replace MDB port group entries. This is useful, for example, when user space wants to add a new source to a source list. Instead of deleting a (*, G) entry and re-adding it with an extended source list (which would result in packet loss), user space can simply replace the current entry. Patches #13-#14 add tests for existing MDB functionality as well as for all new functionality added in this patchset. Future work =========== The VXLAN driver will need to be extended with an MDB so that it could selectively forward IP multicast traffic to NVE switches with interested receivers instead of simply flooding it to all switches as BUM. The idea is to reuse the existing MDB interface for the VXLAN driver in a similar way to how the FDB interface is shared between the bridge and VXLAN drivers. From command line perspective, configuration will look as follows: # bridge mdb add dev br0 port vxlan0 grp 239.1.1.1 permanent \ filter_mode exclude source_list 198.50.100.1,198.50.100.2 # bridge mdb add dev vxlan0 port vxlan0 grp 239.1.1.1 permanent \ filter_mode include source_list 198.50.100.3,198.50.100.4 \ dst 192.0.2.1 dst_port 4789 src_vni 2 # bridge mdb add dev vxlan0 port vxlan0 grp 239.1.1.1 permanent \ filter_mode exclude source_list 198.50.100.1,198.50.100.2 \ dst 192.0.2.2 dst_port 4789 src_vni 2 Where the first command is enabled by this set, but the next two will be the subject of future work. From netlink perspective, the existing PF_BRIDGE/RTM_*MDB messages will be extended to the VXLAN driver. This means that a few new attributes will be added (e.g., 'MDBE_ATTR_SRC_VNI') and that the handlers for these messages will need to move to net/core/rtnetlink.c. The rtnetlink code will call into the appropriate driver based on the ifindex specified in the ancillary header. iproute2 patches can be found here [9]. Changelog ========= Since v1 [10]: * Patch #12: Remove extack from br_mdb_replace_group_sg(). * Patch #12: Change 'nlflags' to u16 and move it after 'filter_mode' to pack the structure. Since RFC [11]: * Patch #6: New patch. * Patch #9: Use an array instead of a list to store source entries. * Patch #10: Use an array instead of list to store source entries. * Patch #10: Drop br_mdb_config_attrs_fini(). * Patch #11: Reject protocol for host entries. * Patch #13: New patch. * Patch #14: New patch. [1] https://datatracker.ietf.org/doc/html/rfc3376 [2] https://www.rfc-editor.org/rfc/rfc3810 [3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6af52ae2ed14a6bc756d5606b29097dfd76740b8 [4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=68d4fd30c83b1b208e08c954cd45e6474b148c87 [5] https://datatracker.ietf.org/doc/html/rfc7432 [6] https://datatracker.ietf.org/doc/html/rfc7432#section-7.2 [7] https://datatracker.ietf.org/doc/html/rfc9251 [8] https://datatracker.ietf.org/doc/html/rfc9251#section-9.1 [9] https://github.com/idosch/iproute2/commits/submit/mdb_v1 [10] https://lore.kernel.org/netdev/20221208152839.1016350-1-idosch@nvidia.com/ [11] https://lore.kernel.org/netdev/20221018120420.561846-1-idosch@nvidia.com/ ==================== Link: https://lore.kernel.org/r/20221210145633.1328511-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We need to check if we have a OS prefix, otherwise we stumble on a metric segv that I'm now seeing in Arnaldo's tree: $ gdb --args perf stat -M Backend true ... Performance counter stats for 'true': 4,712,355 TOPDOWN.SLOTS # 17.3 % tma_core_bound Program received signal SIGSEGV, Segmentation fault. __strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77 77 ../sysdeps/x86_64/multiarch/strlen-evex.S: No such file or directory. (gdb) bt #0 __strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77 #1 0x00007ffff74749a5 in __GI__IO_fputs (str=0x0, fp=0x7ffff75f5680 <_IO_2_1_stderr_>) #2 0x0000555555779f28 in do_new_line_std (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10) at util/stat-display.c:356 #3 0x000055555577a081 in print_metric_std (config=0x555555e077c0 <stat_config>, ctx=0x7fffffffbf10, color=0x0, fmt=0x5555558b77b5 "%8.1f", unit=0x7fffffffbb10 "% tma_memory_bound", val=13.165355724442199) at util/stat-display.c:380 #4 0x00005555557768b6 in generic_metric (config=0x555555e077c0 <stat_config>, metric_expr=0x55555593d5b7 "((CYCLE_ACTIVITY.STALLS_MEM_ANY + EXE_ACTIVITY.BOUND_ON_STORES) / (CYCLE_ACTIVITY.STALLS_TOTAL + (EXE_ACTIVITY.1_PORTS_UTIL + tma_retiring * EXE_ACTIVITY.2_PORTS_UTIL) + EXE_ACTIVITY.BOUND_ON_STORES))"..., metric_events=0x555555f334e0, metric_refs=0x555555ec81d0, name=0x555555f32e80 "TOPDOWN.SLOTS", metric_name=0x555555f26c80 "tma_memory_bound", metric_unit=0x55555593d5b1 "100%", runtime=0, map_idx=0, out=0x7fffffffbd90, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:934 #5 0x0000555555778cac in perf_stat__print_shadow_stats (config=0x555555e077c0 <stat_config>, evsel=0x555555f289d0, avg=4712355, map_idx=0, out=0x7fffffffbd90, metric_events=0x555555e078e8 <stat_config+296>, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:1329 #6 0x000055555577b6a0 in printout (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10, uval=4712355, run=325322, ena=325322, noise=4712355, map_idx=0) at util/stat-display.c:741 #7 0x000055555577bc74 in print_counter_aggrdata (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, s=0, os=0x7fffffffbf10) at util/stat-display.c:838 #8 0x000055555577c1d8 in print_counter (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, os=0x7fffffffbf10) at util/stat-display.c:957 #9 0x000055555577dba0 in evlist__print_counters (evlist=0x555555ec3610, config=0x555555e077c0 <stat_config>, _target=0x555555e01c80 <target>, ts=0x0, argc=1, argv=0x7fffffffe450) at util/stat-display.c:1413 #10 0x00005555555fc821 in print_counters (ts=0x0, argc=1, argv=0x7fffffffe450) at builtin-stat.c:1040 #11 0x000055555560091a in cmd_stat (argc=1, argv=0x7fffffffe450) at builtin-stat.c:2665 #12 0x00005555556b1eea in run_builtin (p=0x555555e11f70 <commands+336>, argc=4, argv=0x7fffffffe450) at perf.c:322 #13 0x00005555556b2181 in handle_internal_command (argc=4, argv=0x7fffffffe450) at perf.c:376 #14 0x00005555556b22d7 in run_argv (argcp=0x7fffffffe27c, argv=0x7fffffffe270) at perf.c:420 #15 0x00005555556b26ef in main (argc=4, argv=0x7fffffffe450) at perf.c:550 (gdb) Fixes: f123b2d ("perf stat: Remove prefix argument in print_metric_headers()") Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com> Link: http://lore.kernel.org/lkml/CAP-5=fUOjSM5HajU9TCD6prY39LbX4OQbkEbtKPPGRBPBN=_VQ@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Unable to handle kernel paging request at virtual address 73657420 when execute [73657420] *pgd=00000000 Internal error: Oops: 80000005 [#1] ARM CPU: 0 PID: 1 Comm: swapper Tainted: G N 6.2.0-rc7-00133-g373f26a81164-dirty #9 Hardware name: Generic DT based system PC is at 0x73657420 LR is at kunit_run_tests+0x3e0/0x5f4 On x86 with GCC 12, the missing array terminators did not seem to matter. Other platforms appear to be more picky. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
code path: ocfs2_ioctl_move_extents ocfs2_move_extents ocfs2_defrag_extent __ocfs2_move_extent + ocfs2_journal_access_di + ocfs2_split_extent //sub-paths call jbd2_journal_restart + ocfs2_journal_dirty //crash by jbs2 ASSERT crash stacks: PID: 11297 TASK: ffff974a676dcd00 CPU: 67 COMMAND: "defragfs.ocfs2" #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01 #1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d #2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d #3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f #4 [ffffb25d8dad3a58] do_trap at ffffffff83833205 #5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6 #6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18 [exception RIP: jbd2_journal_dirty_metadata+0x2ba] RIP: ffffffffc09ca54a RSP: ffffb25d8dad3b70 RFLAGS: 00010207 RAX: 0000000000000000 RBX: ffff9706eedc5248 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffff97337029ea28 RDI: ffff9706eedc5250 RBP: ffff9703c3520200 R8: 000000000f46b0b2 R9: 0000000000000000 R10: 0000000000000001 R11: 00000001000000fe R12: ffff97337029ea28 R13: 0000000000000000 R14: ffff9703de59bf60 R15: ffff9706eedc5250 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2] #8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2] #9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2] Analysis This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call ocfs2_journal_access_di() before ocfs2_journal_dirty() in ocfs2_write_end_nolock()")'. For this bug, jbd2_journal_restart() is called by ocfs2_split_extent() during defragmenting. How to fix For ocfs2_split_extent() can handle journal operations totally by itself. Caller doesn't need to call journal access/dirty pair, and caller only needs to call journal start/stop pair. The fix method is to remove journal access/dirty from __ocfs2_move_extent(). The discussion for this patch: https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html Link: https://lkml.kernel.org/r/20230217003717.32469-1-heming.zhao@suse.com Signed-off-by: Heming Zhao <heming.zhao@suse.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sai Krishna says: ==================== octeontx2: Miscellaneous fixes This patchset includes following fixes. Patch #1 Fix for the race condition while updating APR table Patch #2 Fix end bit position in NPC scan config Patch #3 Fix depth of CAM, MEM table entries Patch #4 Fix in increase the size of DMAC filter flows Patch #5 Fix driver crash resulting from invalid interface type information retrieved from firmware Patch #6 Fix incorrect mask used while installing filters involving fragmented packets Patch #7 Fixes for NPC field hash extract w.r.t IPV6 hash reduction, IPV6 filed hash configuration. Patch #8 Fix for NPC hardware parser configuration destination address hash, IPV6 endianness issues. Patch #9 Fix for skipping mbox initialization for PFs disabled by firmware. Patch #10 Fix disabling packet I/O in case of mailbox timeout. Patch #11 Fix detaching LF resources in case of VF probe fail. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Passing a maximum attribute type to nlmsg_parse() that is larger than the size of the passed policy will result in an out-of-bounds access [1] when the attribute type is used as an index into the policy array. Fix by setting the maximum attribute type according to the policy size, as is already done for RTM_NEWNEXTHOP messages. Add a test case that triggers the bug. No regressions in fib nexthops tests: # ./fib_nexthops.sh [...] Tests passed: 236 Tests failed: 0 [1] BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x1e53/0x2940 Read of size 1 at addr ffffffff99ab4d20 by task ip/610 CPU: 3 PID: 610 Comm: ip Not tainted 6.8.0-rc7-custom-gd435d6e3e161 #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x8f/0xe0 print_report+0xcf/0x670 kasan_report+0xd8/0x110 __nla_validate_parse+0x1e53/0x2940 __nla_parse+0x40/0x50 rtm_del_nexthop+0x1bd/0x400 rtnetlink_rcv_msg+0x3cc/0xf20 netlink_rcv_skb+0x170/0x440 netlink_unicast+0x540/0x820 netlink_sendmsg+0x8d3/0xdb0 ____sys_sendmsg+0x31f/0xa60 ___sys_sendmsg+0x13a/0x1e0 __sys_sendmsg+0x11c/0x1f0 do_syscall_64+0xc5/0x1d0 entry_SYSCALL_64_after_hwframe+0x63/0x6b [...] The buggy address belongs to the variable: rtm_nh_policy_del+0x20/0x40 Fixes: 2118f93 ("net: nexthop: Adjust netlink policy parsing for a new attribute") Reported-by: Eric Dumazet <edumazet@google.com> Closes: https://lore.kernel.org/netdev/CANn89i+UNcG0PJMW5X7gOMunF38ryMh=L1aeZUKH3kL4UdUqag@mail.gmail.com/ Reported-by: syzbot+65bb09a7208ce3d4a633@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/00000000000088981b06133bc07b@google.com/ Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240311162307.545385-4-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
xarray can't support arbitrary page cache size. the largest and supported page cache size is defined as MAX_PAGECACHE_ORDER by commit 099d906 ("mm/filemap: make MAX_PAGECACHE_ORDER acceptable to xarray"). However, it's possible to have 512MB page cache in the huge memory's collapsing path on ARM64 system whose base page size is 64KB. 512MB page cache is breaking the limitation and a warning is raised when the xarray entry is split as shown in the following example. [root@dhcp-10-26-1-207 ~]# cat /proc/1/smaps | grep KernelPageSize KernelPageSize: 64 kB [root@dhcp-10-26-1-207 ~]# cat /tmp/test.c : int main(int argc, char **argv) { const char *filename = TEST_XFS_FILENAME; int fd = 0; void *buf = (void *)-1, *p; int pgsize = getpagesize(); int ret = 0; if (pgsize != 0x10000) { fprintf(stdout, "System with 64KB base page size is required!\n"); return -EPERM; } system("echo 0 > /sys/devices/virtual/bdi/253:0/read_ahead_kb"); system("echo 1 > /proc/sys/vm/drop_caches"); /* Open the xfs file */ fd = open(filename, O_RDONLY); assert(fd > 0); /* Create VMA */ buf = mmap(NULL, TEST_MEM_SIZE, PROT_READ, MAP_SHARED, fd, 0); assert(buf != (void *)-1); fprintf(stdout, "mapped buffer at 0x%p\n", buf); /* Populate VMA */ ret = madvise(buf, TEST_MEM_SIZE, MADV_NOHUGEPAGE); assert(ret == 0); ret = madvise(buf, TEST_MEM_SIZE, MADV_POPULATE_READ); assert(ret == 0); /* Collapse VMA */ ret = madvise(buf, TEST_MEM_SIZE, MADV_HUGEPAGE); assert(ret == 0); ret = madvise(buf, TEST_MEM_SIZE, MADV_COLLAPSE); if (ret) { fprintf(stdout, "Error %d to madvise(MADV_COLLAPSE)\n", errno); goto out; } /* Split xarray entry. Write permission is needed */ munmap(buf, TEST_MEM_SIZE); buf = (void *)-1; close(fd); fd = open(filename, O_RDWR); assert(fd > 0); fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, TEST_MEM_SIZE - pgsize, pgsize); out: if (buf != (void *)-1) munmap(buf, TEST_MEM_SIZE); if (fd > 0) close(fd); return ret; } [root@dhcp-10-26-1-207 ~]# gcc /tmp/test.c -o /tmp/test [root@dhcp-10-26-1-207 ~]# /tmp/test ------------[ cut here ]------------ WARNING: CPU: 25 PID: 7560 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128 Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib \ nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct \ nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 \ ip_set rfkill nf_tables nfnetlink vfat fat virtio_balloon drm fuse \ xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 virtio_net \ sha1_ce net_failover virtio_blk virtio_console failover dimlib virtio_mmio CPU: 25 PID: 7560 Comm: test Kdump: loaded Not tainted 6.10.0-rc7-gavin+ #9 Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : xas_split_alloc+0xf8/0x128 lr : split_huge_page_to_list_to_order+0x1c4/0x780 sp : ffff8000ac32f660 x29: ffff8000ac32f660 x28: ffff0000e0969eb0 x27: ffff8000ac32f6c0 x26: 0000000000000c40 x25: ffff0000e0969eb0 x24: 000000000000000d x23: ffff8000ac32f6c0 x22: ffffffdfc0700000 x21: 0000000000000000 x20: 0000000000000000 x19: ffffffdfc0700000 x18: 0000000000000000 x17: 0000000000000000 x16: ffffd5f3708ffc70 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: ffffffffffffffc0 x10: 0000000000000040 x9 : ffffd5f3708e692c x8 : 0000000000000003 x7 : 0000000000000000 x6 : ffff0000e0969eb8 x5 : ffffd5f37289e378 x4 : 0000000000000000 x3 : 0000000000000c40 x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000 Call trace: xas_split_alloc+0xf8/0x128 split_huge_page_to_list_to_order+0x1c4/0x780 truncate_inode_partial_folio+0xdc/0x160 truncate_inode_pages_range+0x1b4/0x4a8 truncate_pagecache_range+0x84/0xa0 xfs_flush_unmap_range+0x70/0x90 [xfs] xfs_file_fallocate+0xfc/0x4d8 [xfs] vfs_fallocate+0x124/0x2f0 ksys_fallocate+0x4c/0xa0 __arm64_sys_fallocate+0x24/0x38 invoke_syscall.constprop.0+0x7c/0xd8 do_el0_svc+0xb4/0xd0 el0_svc+0x44/0x1d8 el0t_64_sync_handler+0x134/0x150 el0t_64_sync+0x17c/0x180 Fix it by correcting the supported page cache orders, different sets for DAX and other files. With it corrected, 512MB page cache becomes disallowed on all non-DAX files on ARM64 system where the base page size is 64KB. After this patch is applied, the test program fails with error -EINVAL returned from __thp_vma_allowable_orders() and the madvise() system call to collapse the page caches. Link: https://lkml.kernel.org/r/20240715000423.316491-1-gshan@redhat.com Fixes: 6b24ca4 ("mm: Use multi-index entries in the page cache") Signed-off-by: Gavin Shan <gshan@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Acked-by: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Don Dutile <ddutile@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: <stable@vger.kernel.org> [5.17+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
For the *at syscalls, can we get the path from the FD being passed as an argument to be able to reconstruct what is being accessed? (Readlink in /proc/<pid>/fds/# shows the path, why can't this go into the record?) We may need a new auxiliary record type since this is neither the cwd or path.
The text was updated successfully, but these errors were encountered: