From: Insu Yun <wuninsu@gmail.com>
Date: Fri, 12 Feb 2016 06:15:59 +0000 (-0500)
Subject: ext4: fix potential integer overflow
X-Git-Tag: firefly_0821_release~3308^2~117
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=600d41f4ecb53edb540fa00a34a78ea6e5c9f9f7;p=firefly-linux-kernel-4.4.55.git

ext4: fix potential integer overflow

commit 46901760b46064964b41015d00c140c83aa05bcf upstream.

Since sizeof(ext_new_group_data) > sizeof(ext_new_flex_group_data),
integer overflow could be happened.
Therefore, need to fix integer overflow sanitization.

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index ad62d7acc315..34038e3598d5 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -198,7 +198,7 @@ static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned long flexbg_size)
 	if (flex_gd == NULL)
 		goto out3;
 
-	if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_flex_group_data))
+	if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_group_data))
 		goto out2;
 	flex_gd->count = flexbg_size;