[PATCH 4.4 019/137] ext4: fix potential integer overflow

Greg Kroah-Hartman
2016-02-24T04:40:35Z

From: Insu Yun <wuninsu@gmail.com>

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>

---
fs/ext4/resize.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -198,7 +198,7 @@ static struct ext4_new_flex_group_data *
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;