Re: (ITS#6892) Segfault in Syncprov overlay

[hyc@symas.com]

ghola@rebelbase.com wrote:
> Full_Name: Duncan Idaho
> Version: 2.4.25
> OS: RHEL 5.5
> URL: ftp://ftp.openldap.org/incoming/
> Submission from: (NULL) (204.10.36.147)
>
>
> In my configuration slapd segfaults within a few hours repeatably when a NULL
> value is somehow passed as a filter to test_filter in the syncprov overlay.
>
> I'm running "threads 64" as I have 62 consumers connecting and this was required
> to prevent unrelated searches from timing out when all the consumers connect at
> once.
>
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 0x59832940 (LWP 2042)]
> test_filter (op=0x59830770, e=0x2aab11861068, f=0x0) at filterentry.c:69
> 69              if ( f->f_choice&  SLAPD_FILTER_UNDEFINED ) {
> (gdb) bt
> #0  test_filter (op=0x59830770, e=0x2aab11861068, f=0x0) at filterentry.c:69
> #1  0x00000000004db315 in syncprov_matchops (op=0x59831130, opc=0xbc91750,
> saveit=1) at syncprov.c:1314
> #2  0x00000000004db6b5 in syncprov_op_mod (op=0x59831130, rs=<value optimized
> out>) at syncprov.c:2124
> #3  0x000000000047e62a in overlay_op_walk (op=0x59831130, rs=0x59830f40,
> which=op_modify, oi=0x8d7b50, on=0x8dc540) at backover.c:659
> #4  0x000000000047ec07 in over_op_func (op=0x59831130, rs=0x59830f40,
> which=op_modify) at backover.c:721
> #5  0x000000000047404d in syncrepl_updateCookie (si=0x8d74e0, op=0x59831130,
> syncCookie=0x59831aa0) at syncrepl.c:3292
> #6  0x0000000000479d0d in do_syncrep2 (ctx=<value optimized out>, arg=<value
> optimized out>) at syncrepl.c:959
> #7  do_syncrepl (ctx=<value optimized out>, arg=<value optimized out>) at
> syncrepl.c:1455
> #8  0x000000000041f7aa in connection_read_thread (ctx=0x59831d70, argv=<value
> optimized out>) at connection.c:1251
> #9  0x00000000004ec5ec in ldap_int_thread_pool_wrapper (xpool=0x84de50) at
> tpool.c:685
> #10 0x000000301b20673d in start_thread (arg=<value optimized out>) at
> pthread_create.c:301
> #11 0x000000301aad44bd in clone () from /lib64/libc.so.6
>
> Let me know if I can provide more info.

A patch to avoid this particular crash is now in git master. However, it's 
still not clear to me why it occurred. Can you get this info from gdb:
	frame 1
	print *ss


-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/