From 1846430c24d66e85cc58286b3319c82cd54debb2 Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Thu, 25 Jan 2018 11:02:51 -0700 Subject: [PATCH] Btrfs: fix crash due to not cleaning up tree log block's dirty bits 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: v3.12+ Fixes: 681ae50917df ("Btrfs: cleanup reserved space when freeing tree log on error") Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba --- 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 != -- GitLab