Thread: BUG #5731: postmaster sometimes dumps core when handling local connections

The following bug has been logged online:

Bug reference:      5731
Logged by:          Alexander V. Chernikov
Email address:      melifaro@ipfw.ru
PostgreSQL version: 8.4.5
Operating system:   FreeBSD 7.3
Description:        postmaster sometimes dumps core when handling local
connections
Details:

aluminium# gdb `which postgres` postgres.core

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This GDB was configured as "amd64-marcel-freebsd"...
Core was generated by `postgres'.
Program terminated with signal 11, Segmentation fault.
.....
#0  0x0000000000638f1a in ConnCreate (serverFd=4) at postmaster.c:1939

1939            port->gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo));
(gdb) bt
#0  0x0000000000638f1a in ConnCreate (serverFd=4) at postmaster.c:1939
#1  0x0000000000637f88 in ServerLoop () at postmaster.c:1384
#2  0x000000000063777b in PostmasterMain (argc=3, argv=0x7fffffffec00) at
postmaster.c:1040
#3  0x00000000005c06da in main (argc=3, argv=0x7fffffffec00) at main.c:188
(gdb) p port
$1 = (Port *) 0x0


This simple patch seem to fix the problem

--- src/backend/postmaster/postmaster.c.orig    2010-10-27
19:07:42.000000000 +0400
+++ src/backend/postmaster/postmaster.c 2010-10-27 19:08:25.000000000 +0400
@@ -1917,7 +1917,7 @@
                if (port->sock >= 0)
                        StreamClose(port->sock);
                ConnFree(port);
-               port = NULL;
+               return NULL;
        }
        else
        {

On 27.10.2010 18:19, Alexander V. Chernikov wrote:
> Program terminated with signal 11, Segmentation fault.
> .....
> #0  0x0000000000638f1a in ConnCreate (serverFd=4) at postmaster.c:1939
>
> 1939            port->gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo));

Hmm, so you get a crash whenever accept() or one of the other calls in
StreamConnection fails, and the server is compiled with GSSAPI. Funny
that it has gone unnoticed for such a long time, clearly accept() and
friends don't fail very often.

> This simple patch seem to fix the problem

Thanks, patch applied.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com