Commit 28850d25 authored May 04, 2023 by Johannes Thumshirn Committed by Greg Kroah-Hartman Jun 21, 2023

btrfs: handle memory allocation failure in btrfs_csum_one_bio



[ Upstream commit 806570c0bb7b4847828c22c4934fcf2dc8fc572f ]

Since f8a53bb58ec7 ("btrfs: handle checksum generation in the storage
layer") the failures of btrfs_csum_one_bio() are handled via
bio_end_io().

This means, we can return BLK_STS_RESOURCE from btrfs_csum_one_bio() in
case the allocation of the ordered sums fails.

This also fixes a syzkaller report, where injecting a failure into the
kvzalloc() call results in a BUG_ON().

Reported-by:  <syzbot+d8941552e21eac774778@syzkaller.appspotmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent b3158674

fs/btrfs/file-item.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -499,7 +499,9 @@ blk_status_t btrfs_csum_one_bio(struct inode inode, struct bio bio,
		sums = kvzalloc(btrfs_ordered_sum_size(fs_info,
		bytes_left), GFP_KERNEL);
		memalloc_nofs_restore(nofs_flag);
		BUG_ON(!sums); /* -ENOMEM */
		if (!sums)
		return BLK_STS_RESOURCE;

		sums->len = bytes_left;
		ordered = btrfs_lookup_ordered_extent(inode,
		offset);