On Thu, Mar 25, 2021 at 01:08:02PM +0100, David Sterba wrote:
On Thu, Mar 25, 2021 at 07:24:41AM -0400, Sasha Levin wrote:
From: Qu Wenruo wqu@suse.com
[ Upstream commit fbf48bb0b197e6894a04c714728c952af7153bf3 ]
There is a piece of weird code in insert_prealloc_file_extent(), which looks like:
ret = btrfs_qgroup_release_data(inode, file_offset, len); if (ret < 0) return ERR_PTR(ret); if (trans) { ret = insert_reserved_file_extent(trans, inode, file_offset, &stack_fi, true, ret); ... } extent_info.is_new_extent = true; extent_info.qgroup_reserved = ret; ...
Note how the variable @ret is abused here, and if anyone is adding code just after btrfs_qgroup_release_data() call, it's super easy to overwrite the @ret and cause tons of qgroup related bugs.
Fix such abuse by introducing new variable @qgroup_released, so that we won't reuse the existing variable @ret.
Signed-off-by: Qu Wenruo wqu@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org
This patch is a preparatory work and does not make sense for backport standalone. Either this one plus https://lore.kernel.org/linux-btrfs/20210303104152.105877-2-wqu@suse.com/ or neither. And IIRC it does not apply directly and needs some additional review before it can be backported to older code base, so it has no CC: stable tags.
I'll drop it, thanks!