From ba17101b41977f124948e0a7797fdcbb59e19f3e Mon Sep 17 00:00:00 2001
From: Eric Dumazet <dada1@cosmosbay.com>
Date: Mon, 1 Aug 2005 21:11:43 -0700
Subject: [PATCH] [PATCH] sys_set_mempolicy() doesnt check if mode < 0

A kernel BUG() is triggered by a call to set_mempolicy() with a negative
first argument.  This is because the mode is declared as an int, and the
validity check doesnt check < 0 values.  Alternatively, mode could be
declared as unsigned int or unsigned long.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 mm/mempolicy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 1694845526be5..b4eababc81987 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -443,7 +443,7 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
 	struct mempolicy *new;
 	DECLARE_BITMAP(nodes, MAX_NUMNODES);
 
-	if (mode > MPOL_MAX)
+	if (mode < 0 || mode > MPOL_MAX)
 		return -EINVAL;
 	err = get_nodes(nodes, nmask, maxnode, mode);
 	if (err)
-- 
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