From: Chris Wright <chrisw@sous-sol.org>
Date: Fri, 17 Feb 2006 21:59:36 +0000 (-0800)
Subject: [PATCH] sys_mbind sanity checking
X-Git-Tag: v2.6.16-rc4~2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=636f13c174dd7c84a437d3c3e8fa66f03f7fda63;p=linux-2.6

[PATCH] sys_mbind sanity checking

Make sure maxnodes is safe size before calculating nlongs in
get_nodes().

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 323fdcf128..bedfa4f09c 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -808,6 +808,8 @@ static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
 	nodes_clear(*nodes);
 	if (maxnode == 0 || !nmask)
 		return 0;
+	if (maxnode > PAGE_SIZE)
+		return -EINVAL;
 
 	nlongs = BITS_TO_LONGS(maxnode);
 	if ((maxnode % BITS_PER_LONG) == 0)