[syslog-ng] mongodb stats crash

[Balazs Scheidler]

Hi,

I have encountered a fixed crash in 3.5 master in the mongodb() driver,
it aborts in stats_unregister_counter()


it seems that afmongodb_format_stats_instance() returns different values
in init() and deinit().

This is my config:

        mongodb(value-pairs(pair('foo', "$STAMP")) frac-digits(3));

This is the backtrace:


[Thread 0x7ffff7fca700 (LWP 27493) exited]
**
ERROR:/home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/stats.c:302:stats_unregister_counter: assertion failed: (sc && (sc->live_mask & (1 << type)) && &sc->counters[type] == (*counter))

Program received signal SIGABRT, Aborted.
0x00007ffff7275037 in __GI_raise (sig=sig at entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
56	../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0  0x00007ffff7275037 in __GI_raise (sig=sig at entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1  0x00007ffff7278698 in __GI_abort () at abort.c:90
#2  0x00007ffff788e3b6 in g_assertion_message () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007ffff788e914 in g_assertion_message_expr () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007ffff7b69ef8 in stats_unregister_counter (source=533, id=0x61cd10 "d_local#0", instance=0x7ffff4d26c40 <persist_name.15015> "mongodb,127.0.0.1,27017,syslog,messages", type=SC_TYPE_STORED, counter=0x6e4cd0)
    at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/stats.c:302
#5  0x00007ffff7b5b838 in log_threaded_dest_driver_deinit_method (s=0x6e4c10) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/logthrdestdrv.c:162
#6  0x00007ffff7b49014 in log_pipe_deinit (s=0x6e4c10) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/logpipe.h:268
#7  0x00007ffff7b4afad in cfg_tree_stop (self=0x613f30) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/cfg-tree.c:1080
#8  0x00007ffff7b44908 in cfg_deinit (cfg=0x613dc0) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/cfg.c:225
#9  0x00007ffff7b607b1 in main_loop_exit_finish () at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/mainloop.c:646
#10 0x00007ffff7b60407 in main_loop_io_worker_sync_call (func=0x7ffff7b60799 <main_loop_exit_finish>) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/mainloop.c:470
#11 0x00007ffff7b607d0 in main_loop_exit_timer_elapsed (arg=0x0) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/mainloop.c:653
#12 0x00007ffff7b96568 in iv_run_timers () from /home/bazsi/zwa/install/syslog-ng-ose-3.5/lib/libsyslog-ng-3.5.0beta3.so
#13 0x00007ffff7b99230 in iv_main () from /home/bazsi/zwa/install/syslog-ng-ose-3.5/lib/libsyslog-ng-3.5.0beta3.so
#14 0x00007ffff7b60ba7 in main_loop_run () at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/lib/mainloop.c:796
#15 0x0000000000401a67 in main (argc=1, argv=0x7fffffffd648) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/syslog-ng/main.c:269
(gdb) 

Stepping through format_stats_instance() at init time:


Breakpoint 3, afmongodb_dd_format_stats_instance (d=0x6e4c10) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/modules/afmongodb/afmongodb.c:189
189	  MongoDBDestDriver *self = (MongoDBDestDriver *)d;
(gdb) n
192	  if (self->port == MONGO_CONN_LOCAL)
(gdb) p self->port
$1 = 0
(gdb) n
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) l
191	
192	  if (self->port == MONGO_CONN_LOCAL)
193	    g_snprintf(persist_name, sizeof(persist_name),
194	               "mongodb,%s,%s,%s", self->address, self->db, self->coll);
195	  else
196	    g_snprintf(persist_name, sizeof(persist_name),
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
198	  return persist_name;
199	}
200	
(gdb) n
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
198	  return persist_name;
(gdb) p persist_name
$2 = "mongodb,(null),0,syslog,messages", '\000' <repeats 991 times>

At deinit time:

Breakpoint 3, afmongodb_dd_format_stats_instance (d=0x6e4c10) at /home/bazsi/zwa/work/syslog-ng-ose-3.5/syslog-ng-ose/modules/afmongodb/afmongodb.c:189
189	  MongoDBDestDriver *self = (MongoDBDestDriver *)d;
(gdb) n
192	  if (self->port == MONGO_CONN_LOCAL)
(gdb) p self->port
$3 = 27017
(gdb) p self->address
$4 = (gchar *) 0x61d290 "127.0.0.1"
(gdb) n
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
197	               "mongodb,%s,%u,%s,%s", self->address, self->port, self->db, self->coll);
(gdb) 
196	    g_snprintf(persist_name, sizeof(persist_name),
(gdb) 
198	  return persist_name;
(gdb) p persist_name
$5 = "mongodb,127.0.0.1,27017,syslog,messages", '\000' <repeats 984 times>

This patch solves for me, however I'm not 100% certain it's the proper fix and the other 
LogThreadedDestDriver instances might be affected too.

diff --git a/modules/afmongodb/afmongodb.c b/modules/afmongodb/afmongodb.c
index 6504a63..b625c2c 100644
--- a/modules/afmongodb/afmongodb.c
+++ b/modules/afmongodb/afmongodb.c
@@ -516,8 +516,6 @@ afmongodb_dd_init(LogPipe *s)
   GlobalConfig *cfg = log_pipe_get_config(s);
   ValuePairsTransformSet *vpts;
 
-  if (!log_threaded_dest_driver_init_method(s))
-    return FALSE;
 
   log_template_options_init(&self->template_options, cfg);
 
@@ -566,6 +564,9 @@ afmongodb_dd_init(LogPipe *s)
                 evt_tag_str("collection", self->coll),
                 NULL);
 
+  if (!log_threaded_dest_driver_init_method(s))
+    return FALSE;
+
   log_threaded_dest_driver_start(&self->super);
 
   return TRUE;

In case we're moving this to this point, I'd say that the threaded_dest_driver_start() could
be moved into the log_threaded_dest_driver_init_method() function, can't it?

Can you have a look?
Thanks.