From 404bccbcaa7ecb073b4d7c1126efda47b346be4a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 12 Mar 2021 15:25:01 -0500 Subject: [PATCH] btrfs: do proper error handling in record_reloc_root_in_trans Generally speaking this shouldn't ever fail, the corresponding fs root for the reloc root will already be in memory, so we won't get ENOMEM here. However if there is no corresponding root for the reloc root then we could get ENOMEM when we try to allocate it or we could get ENOENT when we look it up and see that it doesn't exist. Convert these BUG_ON()'s into ASSERT()'s and add proper error handling for the case of corruption. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/relocation.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 3c82011..1abe756 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -1971,8 +1971,27 @@ static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, return 0; root = btrfs_get_fs_root(fs_info, reloc_root->root_key.offset, false); - BUG_ON(IS_ERR(root)); - BUG_ON(root->reloc_root != reloc_root); + + /* + * This should succeed, since we can't have a reloc root without having + * already looked up the actual root and created the reloc root for this + * root. + * + * However if there's some sort of corruption where we have a ref to a + * reloc root without a corresponding root this could return ENOENT. + */ + if (IS_ERR(root)) { + ASSERT(0); + return PTR_ERR(root); + } + if (root->reloc_root != reloc_root) { + ASSERT(0); + btrfs_err(fs_info, + "root %llu has two reloc roots associated with it", + reloc_root->root_key.offset); + btrfs_put_root(root); + return -EUCLEAN; + } ret = btrfs_record_root_in_trans(trans, root); btrfs_put_root(root); -- 2.7.4