Patch "xfs: fail _dir_open when readahead fails" has been added to the 4.10-stable tree

This is a note to let you know that I've just added the patch titled

xfs: fail _dir_open when readahead fails

to the 4.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
xfs-fail-_dir_open-when-readahead-fails.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: "Darrick J. Wong" <[email protected]>
Date: Thu, 2 Feb 2017 15:13:58 -0800
Subject: xfs: fail _dir_open when readahead fails

From: Darrick J. Wong <[email protected]>

commit 7a652bbe366464267190c2792a32ce4fff5595ef upstream.

When we open a directory, we try to readahead block 0 of the directory on the assumption that we're going to need it soon. If the bmbt is corrupt, the directory will never be usable and the readahead fails immediately, so we might as well prevent the directory from being opened at all. This prevents a subsequent read or modify operation from hitting it and taking the fs offline.

NOTE: We're only checking for early failures in the block mapping, not the readahead directory block itself.

---
 fs/xfs/libxfs/xfs_da_btree.c |    6 ++----
 fs/xfs/libxfs/xfs_da_btree.h |    2 +-
 fs/xfs/xfs_file.c            |    4 ++--
 3 files changed, 5 insertions(+), 7 deletions(-)

@@ -2633,7 +2633,7 @@ out_free:
 /*
  * Readahead the dir/attr block.
  */
-xfs_daddr_t
+int
 xfs_da_reada_buf(
 	struct xfs_inode	*dp,
 	xfs_dablk_t		bno,

@@ -2664,7 +2664,5 @@ out_free:
 	if (mapp != &map)
 		kmem_free(mapp);
 
-	if (error)
-		return -1;
-	return mappedbno;
+	return error;
 }

@@ -201,7 +201,7 @@ int	xfs_da_read_buf(struct xfs_trans *tr
 			       xfs_dablk_t bno, xfs_daddr_t mappedbno,
 			       struct xfs_buf **bpp, int whichfork,
 			       const struct xfs_buf_ops *ops);
-xfs_daddr_t	xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
+int	xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
 				xfs_daddr_t mapped_bno, int whichfork,
 				const struct xfs_buf_ops *ops);
 int	xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,

@@ -913,9 +913,9 @@ xfs_dir_open(
 	 */
 	mode = xfs_ilock_data_map_shared(ip);
 	if (ip->i_d.di_nextents > 0)
-		xfs_dir3_data_readahead(ip, 0, -1);
+		error = xfs_dir3_data_readahead(ip, 0, -1);
 	xfs_iunlock(ip, mode);
-	return 0;
+	return error;
 }
 
 STATIC int

Patches currently in stable-queue which might be from [email protected] are

queue-4.10/xfs-correct-null-checks-and-error-processing-in-xfs_initialize_perag.patch queue-4.10/xfs-mark-speculative-prealloc-cow-fork-extents-unwritten.patch queue-4.10/xfs-fix-toctou-race-when-locking-an-inode-to-access-the-data-map.patch queue-4.10/xfs-use-iomap-new-flag-for-newly-allocated-delalloc-blocks.patch queue-4.10/xfs-handle-indlen-shortage-on-delalloc-extent-merge.patch queue-4.10/xfs-reject-all-unaligned-direct-writes-to-reflinked-files.patch queue-4.10/xfs-allow-unwritten-extents-in-the-cow-fork.patch queue-4.10/xfs-tune-down-agno-asserts-in-the-bmap-code.patch queue-4.10/xfs-verify-free-block-header-fields.patch queue-4.10/xfs-check-for-obviously-bad-level-values-in-the-bmbt-root.patch queue-4.10/xfs-don-t-fail-xfs_extent_busy-allocation.patch queue-4.10/xfs-sync-eofblocks-scans-under-iolock-are-livelock-prone.patch queue-4.10/xfs-pull-up-iolock-from-xfs_free_eofblocks.patch queue-4.10/xfs-fail-_dir_open-when-readahead-fails.patch queue-4.10/xfs-reset-b_first_retry_time-when-clear-the-retry-status-of-xfs_buf_t.patch queue-4.10/xfs-update-ctime-and-mtime-on-clone-destinatation-inodes.patch queue-4.10/xfs-split-indlen-reservations-fairly-when-under-reserved.patch queue-4.10/xfs-filter-out-obviously-bad-btree-pointers.patch queue-4.10/xfs-use-xfs_icluster_size_fsb-to-calculate-inode-chunk-alignment.patch queue-4.10/xfs-only-reclaim-unwritten-cow-extents-periodically.patch queue-4.10/xfs-try-any-ag-when-allocating-the-first-btree-block-when-reflinking.patch queue-4.10/xfs-fix-and-streamline-error-handling-in-xfs_end_io.patch queue-4.10/xfs-fix-eofblocks-race-with-file-extending-async-dio-writes.patch queue-4.10/xfs-fix-uninitialized-variable-in-_reflink_convert_cow.patch queue-4.10/xfs-don-t-reserve-blocks-for-right-shift-transactions.patch queue-4.10/xfs-use-xfs_icluster_size_fsb-to-calculate-inode-alignment-mask.patch