memory leak in threaded getpwuid_r() usage

[Volkan YAZICI]

Hi,

Trying to use getpwuid_r() in a threaded application. (Code is attached
at the end of the message.) But in the "ps -p <PID> -o rss,size" output
of the program, RSS increases by time while SIZE remains stable.

After exploring the web, I've found some other people
(http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=273051) facing with
the same bug. AFAICS, there's a problem with some versions of the
libnss package. I'd be so appreciated if you can help me to figure out
the source of the problem and how can I solve it.

Tests were made using libc6 2.3.2.ds1-22 and libnss-db 2.2-6.3 on
debian stable (sarge).

Here's the (ps -p <PID> -o rss,size) output of the program:

[BEGIN:output]
$ ./a.out
user_id = 1000, proc_id = 28583
  1  700 46336
  2  704 46336
...
 47  716 46332
 48  716 46332
 49  716 46336
 50  716 46336
[END:output]

And valgrind --leak-check=full output:

[BEGIN:valgrind]
156 (36 direct, 120 indirect) bytes in 1 blocks are definitely lost in
loss record 4 of 9
   at 0x1B90459D: malloc (vg_replace_malloc.c:130)
   by 0x1BA0BEE6: (within /lib/tls/libc-2.3.2.so)
   by 0x1BA0B788: __nss_database_lookup (in /lib/tls/libc-2.3.2.so)
   by 0x1DB70AFB: ???
   by 0x1B9CCD4B: getpwuid_r (in /lib/tls/libc-2.3.2.so)
   by 0x804879A: sub_func (getpwuid.c:43)
   by 0x1B918B62: start_thread (in /lib/tls/libpthread-0.60.so)
   by 0x1B9FC189: clone (in /lib/tls/libc-2.3.2.so)

340 bytes in 5 blocks are possibly lost in loss record 8 of 9
   at 0x1B904F75: calloc (vg_replace_malloc.c:175)
   by 0x1B8F2678: (within /lib/ld-2.3.2.so)
   by 0x1B8F294B: _dl_allocate_tls (in /lib/ld-2.3.2.so)
   by 0x1B91924A: allocate_stack (in /lib/tls/libpthread-0.60.so)
   by 0x1B918C54: pthread_create@@GLIBC_2.1 (in
/lib/tls/libpthread-0.60.so)
   by 0x80488AB: main (getpwuid.c:68)
[END:valgrind]


Regards.

P.S. Please excuse me if this list is the wrong place to ask the
question. But, Debian Bug Tracking System seems like not responsive
about the related report.
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