I was able to crash postgres 6.5.3 when I did an 'alter user' command.
After I started a debugger I found the problem in the timezone handling
of
datetime (my Linux box lost its timezone information, that's how the
problem occurred).

Only 7 bytes are reserved for the timezone, without checking for
boundaries.

Attached is a patch that fixes this problem and emits a NOTICE if a
timezone is encountered that is longer than MAXTZLEN bytes, like this:

Jeroen van Vianen
This commit is contained in:
Bruce Momjian 1999-12-09 05:02:24 +00:00
parent 469cf43fac
commit d65a27f950
2 changed files with 24 additions and 6 deletions

View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/Attic/dt.c,v 1.76 1999/07/17 20:17:55 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/Attic/dt.c,v 1.77 1999/12/09 05:02:24 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -4327,7 +4327,7 @@ EncodeDateTime(struct tm * tm, double fsec, int *tzp, char **tzn, int style, cha
if ((*tzn != NULL) && (tm->tm_isdst >= 0))
{
strcpy((str + 27), " ");
strcpy((str + 28), *tzn);
strncpy((str + 28), *tzn, MAXTZLEN);
}
}
else
@ -4336,7 +4336,7 @@ EncodeDateTime(struct tm * tm, double fsec, int *tzp, char **tzn, int style, cha
if ((*tzn != NULL) && (tm->tm_isdst >= 0))
{
strcpy((str + 24), " ");
strcpy((str + 25), *tzn);
strncpy((str + 25), *tzn, MAXTZLEN);
}
}

View File

@ -4,7 +4,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: nabstime.c,v 1.61 1999/07/17 20:17:57 momjian Exp $
* $Id: nabstime.c,v 1.62 1999/12/09 05:02:24 momjian Exp $
*
*/
#include <ctype.h>
@ -174,7 +174,16 @@ abstime2tm(AbsoluteTime time, int *tzp, struct tm * tm, char *tzn)
*tzp = -tm->tm_gmtoff; /* tm_gmtoff is Sun/DEC-ism */
/* XXX FreeBSD man pages indicate that this should work - tgl 97/04/23 */
if (tzn != NULL)
strcpy(tzn, tm->tm_zone);
{
/* Copy no more than MAXTZLEN bytes of timezone to tzn, in case it
contains an error message, which doesn't fit in the buffer */
strncpy(tzn, tm->tm_zone, MAXTZLEN);
if (strlen(tm->tm_zone) > MAXTZLEN)
{
tzn[MAXTZLEN] = '\0';
elog(NOTICE, "Invalid timezone \'%s\'", tm->tm_zone);
}
}
#elif defined(HAVE_INT_TIMEZONE)
if (tzp != NULL)
#ifdef __CYGWIN__
@ -183,7 +192,16 @@ abstime2tm(AbsoluteTime time, int *tzp, struct tm * tm, char *tzn)
*tzp = (tm->tm_isdst ? (timezone - 3600) : timezone);
#endif
if (tzn != NULL)
strcpy(tzn, tzname[tm->tm_isdst]);
{
/* Copy no more than MAXTZLEN bytes of timezone to tzn, in case it
contains an error message, which doesn't fit in the buffer */
strncpy(tzn, tzname[tm->tm_isdst], MAXTZLEN);
if (strlen(tzname[tm->tm_isdst]) > MAXTZLEN)
{
tzn[MAXTZLEN] = '\0';
elog(NOTICE, "Invalid timezone \'%s\'", tzname[tm->tm_isdst]);
}
}
#else
#error POSIX time support is broken
#endif