Btrfs: use right type to get real comparison

We want to make sure the point is still within the extent item, not to verify
the memory it's pointing to.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 84d0912eecb2..00f9d9f911ca 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1428,7 +1428,7 @@ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb,
                         *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1);
                 }
                 *ptr = (unsigned long)*out_eiref;
-                if ((void *)*ptr >= (void *)ei + item_size)
+                if ((unsigned long)(*ptr) >= (unsigned long)ei + item_size)
                         return -ENOENT;
         }