tasks coverities

[radare]

*** CID 1393487:  Concurrent data access violations  (MISSING_LOCK)
/libr/core/task.c: 294 in r_core_task_sync_begin()
288     /* begin running stuff synchronously on the main task */
289     R_API void r_core_task_sync_begin(RCore *core) {
290     	RCoreTask *task = core->main_task;
291     	task->thread = NULL;
292     	task->cmd = NULL;
293     	task->cmd_log = false;
   CID 1393487:  Concurrent data access violations  (MISSING_LOCK)
   Accessing "task->state" without holding lock "r_th_lock_t.lock". Elsewhere, "r_core_task_t.state" is accessed with "r_th_lock_t.lock" held 2 out of 4 times (2 of these accesses strongly imply that it is necessary).
294     	task->state = R_CORE_TASK_STATE_BEFORE_START;
295     	task_wakeup (task);
296     }
297     
298     /* end running stuff synchronously, initially started with r_core_task_sync_begin() */
299     R_API void r_core_task_sync_end(RCore *core) {

** CID 1393486:  Program hangs  (LOCK)
/libr/core/task.c: 229 in task_wakeup()


________________________________________________________________________________________________________
*** CID 1393486:  Program hangs  (LOCK)
/libr/core/task.c: 229 in task_wakeup()
223     			// and has to be dumped.
224     			core->main_task->cons = r_cons_dump ();
225     		}
226     		r_cons_load (current->cons);
227     		current->cons = NULL;
228     	}
   CID 1393486:  Program hangs  (LOCK)
   Returning without unlocking "current->dispatch_lock->lock".
229     }
230     
231     R_API void r_core_task_continue(RCoreTask *t) {
232     	r_core_task_schedule (t, R_CORE_TASK_STATE_RUNNING);
233     }
234     

** CID 1393485:  Incorrect expression  (CONSTANT_EXPRESSION_RESULT)
/libr/core/task.c: 104 in r_core_task_new()


________________________________________________________________________________________________________
*** CID 1393485:  Incorrect expression  (CONSTANT_EXPRESSION_RESULT)
/libr/core/task.c: 104 in r_core_task_new()
98     	task->thread = NULL;
99     	task->cmd = cmd ? strdup (cmd) : NULL;
100     	task->cmd_log = false;
101     	task->res = NULL;
102     	task->dispatch_cond = r_th_cond_new ();
103     	task->dispatch_lock = r_th_lock_new (false);
   CID 1393485:  Incorrect expression  (CONSTANT_EXPRESSION_RESULT)
   The expression "!task->dispatch_cond || !task->dispatch_cond" does not accomplish anything because it evaluates to either of its identical operands, "!task->dispatch_cond".
104     	if (!task->dispatch_cond || !task->dispatch_cond) {
105     		goto hell;
106     	}
107     
108     	task->id = core->task_id_next++;
109     	task->state = R_CORE_TASK_STATE_BEFORE_START;

[radare]

cc @thestr4ng3r

[thestr4ng3r]

Noted. I'll take a look at it.

[thestr4ng3r]

The second one about current->dispatch_lock is explicitly done like this since that is the lock for the condition variable, which must stay locked there.
Is there a way to explicitly ignore errors in coverity?

[radare]

yes, there are comments for coverity, but we can also ignore them without adding any comment :P

…

On 19 Jun 2018, at 19:49, Florian Märkl ***@***.***> wrote: The second one about current->dispatch_lock is explicitly done like this since that is the lock for the condition variable, which must stay locked there. Is there a way to explicitly ignore errors in coverity? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#10401 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA3-lhaVMrZ9G5_4rpXQ_NLHZgvyGElsks5t-TmwgaJpZM4UtCdA>.

[XVilka]

@thestr4ng3r checkout also this please:

gdb$ run -d /bin/ls
Starting program: /usr/bin/r2 -d /bin/ls
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Process with PID 24129 started...
= attach 24129 24129
bin.baddr 0x555555554000
Using 0x555555554000
asm.bits 64
[0x7ffff7dd9000]> db main
[0x7ffff7dd9000]> dc
hit breakpoint at: 555555557ac0
[0x555555557ac0]> dmh
Warning: glibc library with symbol main_arena could not be found. Is libc6-dbg installed?

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff4152145 in r_list_pop_head () from /usr/lib64/libr_util.so
gdb$ bt
#0  0x00007ffff4152145 in r_list_pop_head () from /usr/lib64/libr_util.so
#1  0x00007ffff7b5fa9f in r_core_task_schedule () from /usr/lib64/libr_core.so
#2  0x00007ffff73de679 in r_cons_is_breaked () from /usr/lib64/libr_cons.so
#3  0x00007ffff7b07297 in ?? () from /usr/lib64/libr_core.so
#4  0x00007ffff7b37d7d in r_cmd_call () from /usr/lib64/libr_core.so
#5  0x00007ffff7b0541f in ?? () from /usr/lib64/libr_core.so
#6  0x00007ffff7ac69ba in ?? () from /usr/lib64/libr_core.so
#7  0x00007ffff7ac6ec7 in r_core_cmd () from /usr/lib64/libr_core.so
#8  0x00007ffff7aa517d in r_core_prompt () from /usr/lib64/libr_core.so
#9  0x0000555555558ad9 in ?? ()
#10 0x00007ffff3b3f9f7 in __libc_start_main () from /lib64/libc.so.6
#11 0x0000555555559eca in ?? ()
gdb$ 

[thestr4ng3r]

Seems to be this issue: #10387
If cleaning and re-compiling does not help, maybe reopen that one.

[XVilka]

@thestr4ng3r cleaned up everything, took a shower and vacuumed floor - crash is here still.

[thestr4ng3r]

Crash is fixed, I think this issue can be closed.