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Date: Mon, 10 Jul 2006 09:37:32 -0600
From: "Adam Jerome" <abj@novell.com>
To: <linux-kernel@vger.kernel.org>
Subject: [PATCH 001/001] /fs/proc/: 'larger than buffer size' memory
	accesses by clear_user()
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From: Adam B. Jerome <abj@novell.com>

This patch addresses potential 'larger than buffer size' memory accesses by clear_user().
Without this patch, this call to clear_user() can attempt to clear too many (tsz) bytes
resulting in a wrong (-EFAULT) return code by read_kcore().
Signed-off-by: Adam B. Jerome <abj@novell.com>
---

I do not subscribe to the list. Please CC posted answers/comments CC me <abj@novell.com>.
Thanks; -adam

diff -urpN linux-2.6-git/fs/proc/kcore.c linux-2.6-cur/fs/proc/kcore.c
--- linux-2.6-git/fs/proc/kcore.c	2006-07-07 15:39:23.000000000 -0600
+++ linux-2.6-cur/fs/proc/kcore.c	2006-07-07 16:11:58.000000000 -0600
@@ -384,7 +384,7 @@ read_kcore(struct file *file, char __use
 				 */
 				if (n) { 
 					if (clear_user(buffer + tsz - n,
-								tsz - n))
+								n))
 						return -EFAULT;
 				}
 			} else {