7.4.5 / 7.4.6 crash (pg_hba.conf issue)

Rod Taylor <pg@rbt.ca> writes:

I've run across a bug in pg_hba.conf routines which is repeatable in
both 32bit intel on Linux and 64bit AMD on FreeBSD with both 7.4.5 and
7.4.6. It results in the postmaster crashing which is quite annoying
when it leaves behind it's children.

Off-by-one memory allocation problem --- it only bites you if the string
lengths are just right, which probably explains the lack of prior
reports even though the bug has been there since 7.3. Simplest fix is

Index: hba.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/libpq/hba.c,v
retrieving revision 1.87.2.4
retrieving revision 1.87.2.5
diff -c -r1.87.2.4 -r1.87.2.5
*** hba.c	13 Apr 2003 04:07:31 -0000	1.87.2.4
--- hba.c	17 Nov 2004 19:54:53 -0000	1.87.2.5
***************
*** 281,287 ****
  		{
  			if (strlen(comma_str))
  			{
! 				comma_str = repalloc(comma_str, strlen(comma_str) + 1);
  				strcat(comma_str, MULTI_VALUE_SEP);
  			}
  			comma_str = repalloc(comma_str,
--- 281,287 ----
  		{
  			if (strlen(comma_str))
  			{
! 				comma_str = repalloc(comma_str, strlen(comma_str) + 1 + 1);
  				strcat(comma_str, MULTI_VALUE_SEP);
  			}
  			comma_str = repalloc(comma_str,

regards, tom lane

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Hi,

On Wed, 17 Nov 2004, Tom Lane wrote:

Off-by-one memory allocation problem --- it only bites you if the string
lengths are just right, which probably explains the lack of prior
reports even though the bug has been there since 7.3.

Is this worth new dot releases?

Regards,
- --
Devrim GUNDUZ
devrim~gunduz.org devrim.gunduz~linux.org.tr
http://www.tdmsoft.com
http://www.gunduz.org
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Devrim GUNDUZ <devrim@gunduz.org> writes:

Off-by-one memory allocation problem --- it only bites you if the string
lengths are just right, which probably explains the lack of prior
reports even though the bug has been there since 7.3.

Is this worth new dot releases?

I'd say not.

regards, tom lane

Tom Lane wrote:

Devrim GUNDUZ <devrim@gunduz.org> writes:

Off-by-one memory allocation problem --- it only bites you if the string
lengths are just right, which probably explains the lack of prior
reports even though the bug has been there since 7.3.

Is this worth new dot releases?

I'd say not.

At my knowledge Postgres can read that file even if it's writable by
anyone ( I can not test right now or look at the code), if this is the
case then this is a sort of serious bug :-(

Regards
Gaetano Mendola