fix-potential-integer-overflow

   1 ext4: fix potential integer overflow
   2
   3 From: Insu Yun <wuninsu@gmail.com>
   4
   5 Since sizeof(ext_new_group_data) > sizeof(ext_new_flex_group_data),
   6 integer overflow could be happened.
   7 Therefore, need to fix integer overflow sanitization.
   8
   9 Cc: stable@vger.kernel.org
  10 Signed-off-by: Insu Yun <wuninsu@gmail.com>
  11 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  12 ---
  13  fs/ext4/resize.c | 2 +-
  14  1 file changed, 1 insertion(+), 1 deletion(-)
  15
  16 diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
  17 index ad62d7a..34038e3 100644
  18 --- a/fs/ext4/resize.c
  19 +++ b/fs/ext4/resize.c
  20 @@ -198,7 +198,7 @@ static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned long flexbg_size)
  21         if (flex_gd == NULL)
  22                 goto out3;
  23
  24 -       if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_flex_group_data))
  25 +       if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_group_data))
  26                 goto out2;
  27         flex_gd->count = flexbg_size;
  28
  29 --
  30 1.9.1
  31
  32