fix-ext4_xattr_cmp

   1 ext4: fix ext4_xattr_cmp()
   2
   3 From: Tahsin Erdogan <tahsin@google.com>
   4
   5 When a xattr entry refers to an external inode, the value data is not
   6 available in the inline area so we should not attempt to read it using
   7 value offset.
   8
   9 Signed-off-by: Tahsin Erdogan <tahsin@google.com>
  10 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  11 ---
  12  fs/ext4/xattr.c | 3 ++-
  13  1 file changed, 2 insertions(+), 1 deletion(-)
  14
  15 diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
  16 index 9c243b3510b7..739f73a5a345 100644
  17 --- a/fs/ext4/xattr.c
  18 +++ b/fs/ext4/xattr.c
  19 @@ -2169,7 +2169,8 @@ ext4_xattr_cmp(struct ext4_xattr_header *header1,
  20                     entry1->e_value_inum != entry2->e_value_inum ||
  21                     memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
  22                         return 1;
  23 -               if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
  24 +               if (!entry1->e_value_inum &&
  25 +                   memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
  26                            (char *)header2 + le16_to_cpu(entry2->e_value_offs),
  27                            le32_to_cpu(entry1->e_value_size)))
  28                         return 1;
  29 --
  30 2.13.1.611.g7e3b11ae1-goog
  31
  32