From: kirjanov@gmail.com <kirjanov@gmail.com>
Date: Sat, 15 May 2010 16:32:34 +0000 (-0400)
Subject: lib/btree: fix possible NULL pointer dereference
X-Git-Tag: v2.6.34~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=43aa7ac736a4e21aae4882bd8f7c67403aed45b8;p=platform%2Fkernel%2Flinux-stable.git

lib/btree: fix possible NULL pointer dereference

mempool_alloc() can return null in atomic case.

Signed-off-by: Denis Kirjanov <kirjanov@gmail.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/lib/btree.c b/lib/btree.c
index 41859a8..c9c6f03 100644
--- a/lib/btree.c
+++ b/lib/btree.c
@@ -95,7 +95,8 @@ static unsigned long *btree_node_alloc(struct btree_head *head, gfp_t gfp)
 	unsigned long *node;
 
 	node = mempool_alloc(head->mempool, gfp);
-	memset(node, 0, NODESIZE);
+	if (likely(node))
+		memset(node, 0, NODESIZE);
 	return node;
 }