The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f96d44743a44e3332f75d23d2075bb8270900e1d Mon Sep 17 00:00:00 2001

From: Josef Bacik josef@toxicpanda.com Date: Wed, 19 May 2021 11:26:25 -0400 Subject: [PATCH] btrfs: check error value from btrfs_update_inode in tree log

Error injection testing uncovered a case where we ended up with invalid link counts on an inode. This happened because we failed to notice an error when updating the inode while replaying the tree log, and committed the transaction with an invalid file system.

Fix this by checking the return value of btrfs_update_inode. This resolved the link count errors I was seeing, and we already properly handle passing up the error values in these paths.

CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 375c4642f480..e4820e88cba0 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1574,7 +1574,9 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans, if (ret) goto out;

- btrfs_update_inode(trans, root, BTRFS_I(inode)); + ret = btrfs_update_inode(trans, root, BTRFS_I(inode)); + if (ret) + goto out; }

ref_ptr = (unsigned long)(ref_ptr + ref_struct_size) + namelen; @@ -1749,7 +1751,9 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,

if (nlink != inode->i_nlink) { set_nlink(inode, nlink); - btrfs_update_inode(trans, root, BTRFS_I(inode)); + ret = btrfs_update_inode(trans, root, BTRFS_I(inode)); + if (ret) + goto out; } BTRFS_I(inode)->index_cnt = (u64)-1;