Squashfs: fix failure to unlock pages on decompress error

Direct decompression into the page cache.  If we fall back
to using an intermediate buffer (because we cannot grab all the
page cache pages) and we get a decompress fail, we forgot to
release the pages.

Reported-by: Roman Peniaev <r.peniaev@gmail.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>

diff --git a/fs/squashfs/file_direct.c b/fs/squashfs/file_direct.c
index 2943b2bfae482ac83d352f317af4c074ce6597ae..62a0de6632e1aa3c8de599e19db3f8d7e2a383e2 100644 (file)
--- a/fs/squashfs/file_direct.c
+++ b/fs/squashfs/file_direct.c
@@ -84,6 +84,9 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize)
                 */
                res = squashfs_read_cache(target_page, block, bsize, pages,
                                                                page);
+               if (res < 0)
+                       goto mark_errored;
+
                goto out;
        }
 
@@ -119,7 +122,7 @@ mark_errored:
         * dealt with by the caller
         */
        for (i = 0; i < pages; i++) {
-               if (page[i] == target_page)
+               if (page[i] == NULL || page[i] == target_page)
                        continue;
                flush_dcache_page(page[i]);
                SetPageError(page[i]);