ext4: bail out from make_indexed_dir() on first error

When ext4_handle_dirty_dx_node() or ext4_handle_dirty_dirent_node()
fail, there's really something wrong with the fs and there's no point in
continuing further. Just return error from make_indexed_dir() in that
case. Also initialize frames array so that if we return early due to
error, dx_release() doesn't try to dereference uninitialized memory
(which could happen also due to error in do_split()).

Coverity-id: 741300
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

1 files changed, 18 insertions, 10 deletions

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 123798c5ac31..426211882f72 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1816,31 +1816,39 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
                 hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
         hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
         ext4fs_dirhash(name, namelen, &hinfo);
+        memset(frames, 0, sizeof(frames));
         frame = frames;
         frame->entries = entries;
         frame->at = entries;
         frame->bh = bh;
         bh = bh2;
 
-        ext4_handle_dirty_dx_node(handle, dir, frame->bh);
-        ext4_handle_dirty_dirent_node(handle, dir, bh);
+        retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
+        if (retval)
+                goto out_frames;        
+        retval = ext4_handle_dirty_dirent_node(handle, dir, bh);
+        if (retval)
+                goto out_frames;        
 
         de = do_split(handle,dir, &bh, frame, &hinfo);
         if (IS_ERR(de)) {
-                /*
-                 * Even if the block split failed, we have to properly write
-                 * out all the changes we did so far. Otherwise we can end up
-                 * with corrupted filesystem.
-                 */
-                ext4_mark_inode_dirty(handle, dir);
-                dx_release(frames);
-                return PTR_ERR(de);
+                retval = PTR_ERR(de);
+                goto out_frames;
         }
         dx_release(frames);
 
         retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
         brelse(bh);
         return retval;
+out_frames:
+        /*
+         * Even if the block split failed, we have to properly write
+         * out all the changes we did so far. Otherwise we can end up
+         * with corrupted filesystem.
+         */
+        ext4_mark_inode_dirty(handle, dir);
+        dx_release(frames);
+        return retval;
 }
 
 /*