[PATCH] libnl: don't use out-of-scope buffer

[Andrey Vagin]

From: Andrew Vagin <avagin at virtuozzo.com>

The control message buffer is desclared in the if body
and then this buffer is used outside.

Signed-off-by: Andrew Vagin <avagin at virtuozzo.com>
---
 lib/nl.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/nl.c b/lib/nl.c
index cba4217..493291a 100644
--- a/lib/nl.c
+++ b/lib/nl.c
@@ -395,11 +395,14 @@ int nl_send_iovec(struct nl_sock *sk, struct nl_msg *msg, struct iovec *iov, uns
 	/* Add credentials if present. */
 	creds = nlmsg_get_creds(msg);
 	if (creds != NULL) {
-		char buf[CMSG_SPACE(sizeof(struct ucred))];
+		int len = CMSG_SPACE(sizeof(struct ucred));
 		struct cmsghdr *cmsg;
+		char *buf;
+
+		buf = alloca(len);
 
 		hdr.msg_control = buf;
-		hdr.msg_controllen = sizeof(buf);
+		hdr.msg_controllen = len;
 
 		cmsg = CMSG_FIRSTHDR(&hdr);
 		cmsg->cmsg_level = SOL_SOCKET;
-- 
2.4.3