From 362e6663ef2369d77251496d865ad02a2376f962 Mon Sep 17 00:00:00 2001
From: Jason Baron <jbaron@redhat.com>
Date: Wed, 15 Oct 2008 22:01:52 -0700
Subject: [PATCH] exec.c, compat.c: fix count(), compat_count() bounds checking

With MAX_ARG_STRINGS set to 0x7FFFFFFF, and being passed to 'count()' and
compat_count(), it would appear that the current max bounds check of
fs/exec.c:394:

	if(++i > max)
		return -E2BIG;

would never trigger. Since 'i' is of type int, so values would wrap and the
function would continue looping.

Simple fix seems to be chaning ++i to i++ and checking for '>='.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Ollie Wild" <aaw@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 fs/compat.c | 2 +-
 fs/exec.c   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/compat.c b/fs/compat.c
index 075d0509970d..aae13d31612f 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1239,7 +1239,7 @@ static int compat_count(compat_uptr_t __user *argv, int max)
 			if (!p)
 				break;
 			argv++;
-			if(++i > max)
+			if (i++ >= max)
 				return -E2BIG;
 		}
 	}
diff --git a/fs/exec.c b/fs/exec.c
index cecee501ce78..7b5ed50eadeb 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -391,7 +391,7 @@ static int count(char __user * __user * argv, int max)
 			if (!p)
 				break;
 			argv++;
-			if(++i > max)
+			if (i++ >= max)
 				return -E2BIG;
 			cond_resched();
 		}
-- 
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