[PATCH] Initialize nscd stats data [BZ #17892]

Siddhesh Poyarekar siddhesh@redhat.com
Wed Jan 28 09:13:00 GMT 2015


Hi,

nscd stats data that is sent from the daemon to the binary invoked with
'nscd -g' does not always initialize selinux data.  Valgrind complains
about it, so just initialize the entire struct once to get rid of that
warning.  I haven't done a full analysis of the code changed, but the
net change in the code size of the send_stats function is just 2
bytes.  The valgrind warning:

#: valgrind nscd -d
==11384== Memcheck, a memory error detector
==11384== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==11384== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info
==11384== Command: nscd -d
==11384== 
Fri 25 Apr 2014 10:34:53 AM CEST - 11384: handle_request: request received (Version = 2) from PID 11396
Fri 25 Apr 2014 10:34:53 AM CEST - 11384:       GETSTAT
==11384== Thread 6:
==11384== Syscall param socketcall.sendto(msg) points to uninitialised byte(s)
==11384==    at 0x4E4ACDC: send (in /lib64/libpthread-2.12.so)
==11384==    by 0x11AF6B: send_stats (in /usr/sbin/nscd)
==11384==    by 0x112F75: nscd_run_worker (in /usr/sbin/nscd)
==11384==    by 0x4E439D0: start_thread (in /lib64/libpthread-2.12.so)
==11384==    by 0x599AB6C: clone (in /lib64/libc-2.12.so)
==11384==  Address 0x15708395 is on thread 6's stack

OK to commit to 2.21?

Siddhesh

	[BZ #17892]
	* nscd/nscd_stat.c (send_stats): Initialize DATA.

diff --git a/nscd/nscd_stat.c b/nscd/nscd_stat.c
index 0f1f3c0..7aaa21b 100644
--- a/nscd/nscd_stat.c
+++ b/nscd/nscd_stat.c
@@ -94,6 +94,8 @@ send_stats (int fd, struct database_dyn dbs[lastdb])
   struct statdata data;
   int cnt;
 
+  memset (&data, 0, sizeof (data));
+
   memcpy (data.version, compilation, sizeof (compilation));
   data.debug_level = debug_level;
   data.runtime = time (NULL) - start_time;



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