From: Liu Bo <bo.li.liu@oracle.com>
Date: Thu, 25 Jan 2018 11:02:51 -0700
Subject: Btrfs: fix crash due to not cleaning up tree log block's dirty bits
Git-commit: 1846430c24d66e85cc58286b3319c82cd54debb2
Patch-mainline: v4.16-rc2
References: bsc#1083000
In cases that the whole fs flips into readonly status due to failures in
critical sections, then log tree's blocks are still dirty, and this leads
to a crash during umount time, the crash is about use-after-free,
umount
-> close_ctree
-> stop workers
-> iput(btree_inode)
-> iput_final
-> write_inode_now
-> ...
-> queue job on stop'd workers
cc: <stable@vger.kernel.org> v3.12+
Fixes: 681ae50917df ("Btrfs: cleanup reserved space when freeing tree log on error")
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>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
fs/btrfs/tree-log.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index ee1aaed1330e..1920c2149f88 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2471,6 +2471,9 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
clean_tree_block(fs_info, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
+ } else {
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
+ clear_extent_buffer_dirty(next);
}
WARN_ON(root_owner !=
@@ -2551,6 +2554,9 @@ static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
clean_tree_block(fs_info, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
+ } else {
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
+ clear_extent_buffer_dirty(next);
}
WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
@@ -2629,6 +2635,9 @@ static int walk_log_tree(struct btrfs_trans_handle *trans,
clean_tree_block(fs_info, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
+ } else {
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
+ clear_extent_buffer_dirty(next);
}
WARN_ON(log->root_key.objectid !=