[PATCH] passfd: fix use of uninitialised variable

[Pavel Hrdina]

This was found by running libvirt using valgrind. Commit ee195daf
introduced passfd code.

==7533== Syscall param sendmsg(msg.msg_control) points to uninitialised byte(s)
==7533==    at 0x8C728FD: ??? (in /lib64/libpthread-2.19.so)
==7533==    by 0x54F04D1: sendfd (passfd.c:86)
==7533==    by 0x5437881: virNetSocketSendFD (virnetsocket.c:1766)
==7533==    by 0x542C328: virNetServerClientDispatchWrite 
(virnetserverclient.c:1271)
==7533==    by 0x542C328: virNetServerClientDispatchEvent 
(virnetserverclient.c:1371)
==7533==    by 0x52CA076: virEventPollDispatchHandles (vireventpoll.c:508)
==7533==    by 0x52CA076: virEventPollRunOnce (vireventpoll.c:657)
==7533==    by 0x52C8581: virEventRunDefaultImpl (virevent.c:308)
==7533==    by 0x1578FC: virNetServerRun (virnetserver.c:1139)
==7533==    by 0x11E3EC: main (libvirtd.c:1491)
==7533==  Address 0xffefff3f4 is on thread 1's stack
==7533==  in frame #1, created by sendfd (passfd.c:51)

Signed-off-by: Pavel Hrdina <address@hidden>
---
 lib/passfd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/passfd.c b/lib/passfd.c
index 1958776..d832268 100644
--- a/lib/passfd.c
+++ b/lib/passfd.c
@@ -54,7 +54,7 @@ sendfd (int sock, int fd)
   struct msghdr msg;
 # ifdef CMSG_FIRSTHDR
   struct cmsghdr *cmsg;
-  char buf[CMSG_SPACE (sizeof fd)];
+  char buf[CMSG_SPACE (sizeof fd)] = "";
 # endif
 
   /* send at least one char */
-- 
2.0.5