Btrfs: lzo: compressed data size must be less then input size

Logic already skips if compression makes data bigger, let's sync lzo
with zlib and also return error if compressed size is equal to
input size.

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c
index a554856a5f8a6f45d61a83906c8d9ee3869641c0..7e8b0d6a7961f355302da4567387c4f427099f42 100644 (file)
--- a/fs/btrfs/lzo.c
+++ b/fs/btrfs/lzo.c
@@ -230,8 +230,10 @@ static int lzo_compress_pages(struct list_head *ws,
                in_len = min(bytes_left, PAGE_SIZE);
        }
 
-       if (tot_out > tot_in)
+       if (tot_out >= tot_in) {
+               ret = -E2BIG;
                goto out;
+       }
 
        /* store the size of all chunks of compressed data */
        cpage_out = kmap(pages[0]);