Patch "Btrfs: fix deadlock in run_delalloc_nocow" has been added to the 4.15-stable tree

Patch "Btrfs: fix deadlock in run_delalloc_nocow" has been added to the 4.15-stable tree

[gregkh]

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

    Btrfs: fix deadlock in run_delalloc_nocow

to the 4.15-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:
     btrfs-fix-deadlock-in-run_delalloc_nocow.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From e89166990f11c3f21e1649d760dd35f9e410321c Mon Sep 17 00:00:00 2001
From: Liu Bo <bo.li.liu@oracle.com>
Date: Thu, 25 Jan 2018 11:02:50 -0700
Subject: Btrfs: fix deadlock in run_delalloc_nocow

From: Liu Bo <bo.li.liu@oracle.com>

commit e89166990f11c3f21e1649d760dd35f9e410321c upstream.

@cur_offset is not set back to what it should be (@cow_start) if
btrfs_next_leaf() returns something wrong, and the range [cow_start,
cur_offset) remains locked forever.

cc: <stable@vger.kernel.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/btrfs/inode.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1330,8 +1330,11 @@ next_slot:
 		leaf = path->nodes[0];
 		if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 			ret = btrfs_next_leaf(root, path);
-			if (ret < 0)
+			if (ret < 0) {
+				if (cow_start != (u64)-1)
+					cur_offset = cow_start;
 				goto error;
+			}
 			if (ret > 0)
 				break;
 			leaf = path->nodes[0];


Patches currently in stable-queue which might be from bo.li.liu@oracle.com are

queue-4.15/btrfs-fix-btrfs_evict_inode-to-handle-abnormal-inodes-correctly.patch
queue-4.15/btrfs-fix-crash-due-to-not-cleaning-up-tree-log-block-s-dirty-bits.patch
queue-4.15/btrfs-fix-use-after-free-on-root-orphan_block_rsv.patch
queue-4.15/btrfs-fix-extent-state-leak-from-tree-log.patch
queue-4.15/btrfs-fix-unexpected-eexist-when-creating-new-inode.patch
queue-4.15/btrfs-fix-deadlock-in-run_delalloc_nocow.patch