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 fa7d2e668c3ac0ebaaf98ccd9c7d34a5b6bef6d4..cf0a70486618d6c2e0bda9497c5a7aa900d6a332 100644 (file)
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -181,7 +181,7 @@ 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;