From 4867268c57ff709a7b6b86ae6f6537d846d1443a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 23 Sep 2016 13:23:28 +0200 Subject: [PATCH] Btrfs: don't BUG() during drop snapshot Really there's lots of things that can go wrong here, kill all the BUG_ON()'s and replace the logic ones with ASSERT()'s and return EIO instead. Signed-off-by: Josef Bacik [ switched to btrfs_err, errors go to common label ] Reviewed-by: Liu Bo Signed-off-by: David Sterba --- fs/btrfs/extent-tree.c | 38 +++++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index a23597f6d3cd..11802eaaab54 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -8886,15 +8886,13 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, ret = btrfs_lookup_extent_info(trans, root, bytenr, level - 1, 1, &wc->refs[level - 1], &wc->flags[level - 1]); - if (ret < 0) { - btrfs_tree_unlock(next); - free_extent_buffer(next); - return ret; - } + if (ret < 0) + goto out_unlock; if (unlikely(wc->refs[level - 1] == 0)) { btrfs_err(root->fs_info, "Missing references."); - BUG(); + ret = -EIO; + goto out_unlock; } *lookup_info = 0; @@ -8946,7 +8944,12 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, } level--; - BUG_ON(level != btrfs_header_level(next)); + ASSERT(level == btrfs_header_level(next)); + if (level != btrfs_header_level(next)) { + btrfs_err(root->fs_info, "mismatched level"); + ret = -EIO; + goto out_unlock; + } path->nodes[level] = next; path->slots[level] = 0; path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING; @@ -8961,8 +8964,15 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) { parent = path->nodes[level]->start; } else { - BUG_ON(root->root_key.objectid != + ASSERT(root->root_key.objectid == btrfs_header_owner(path->nodes[level])); + if (root->root_key.objectid != + btrfs_header_owner(path->nodes[level])) { + btrfs_err(root->fs_info, + "mismatched block owner"); + ret = -EIO; + goto out_unlock; + } parent = 0; } @@ -8977,12 +8987,18 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, } ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent, root->root_key.objectid, level - 1, 0); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + goto out_unlock; } + + *lookup_info = 1; + ret = 1; + +out_unlock: btrfs_tree_unlock(next); free_extent_buffer(next); - *lookup_info = 1; - return 1; + + return ret; } /* -- 2.45.2