Commit 274295c6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'for-5.19/dm-fixes-3' of... 

Merge tag 'for-5.19/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix a race in DM core's dm_start_io_acct that could result in double
   accounting for abnormal IO (e.g. discards, write zeroes, etc).

 - Fix a use-after-free in DM core's dm_put_live_table_bio.

 - Fix a race for REQ_NOWAIT bios being issued despite no support from
   underlying DM targets (due to DM table reload at an "unlucky" time)

 - Fix access beyond allocated bitmap in DM mirror's log.

* tag 'for-5.19/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm mirror log: round up region bitmap size to BITS_PER_LONG
  dm: fix narrow race for REQ_NOWAIT bios being issued despite no support
  dm: fix use-after-free in dm_put_live_table_bio
  dm: fix race in dm_start_io_acct
parents a96e902b 85e123c2

drivers/md/dm-log.c

+1 −2
Original line number Diff line number Diff line
@@ -415,8 +415,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, 
	/*

	 * Work out how many "unsigned long"s we need to hold the bitset.

	 */

	bitset_size = dm_round_up(region_count,

				  sizeof(*lc->clean_bits) << BYTE_SHIFT);

	bitset_size = dm_round_up(region_count, BITS_PER_LONG);

	bitset_size >>= BYTE_SHIFT;



	lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits);

drivers/md/dm.c

+17 −7
Original line number Diff line number Diff line
@@ -555,6 +555,10 @@ static void dm_start_io_acct(struct dm_io *io, struct bio *clone) 
		unsigned long flags;

		/* Can afford locking given DM_TIO_IS_DUPLICATE_BIO */

		spin_lock_irqsave(&io->lock, flags);

		if (dm_io_flagged(io, DM_IO_ACCOUNTED)) {

			spin_unlock_irqrestore(&io->lock, flags);

			return;

		}

		dm_io_set_flag(io, DM_IO_ACCOUNTED);

		spin_unlock_irqrestore(&io->lock, flags);

	}
@@ -711,18 +715,18 @@ static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) 
}



static inline struct dm_table *dm_get_live_table_bio(struct mapped_device *md,

						     int *srcu_idx, struct bio *bio)

						     int *srcu_idx, unsigned bio_opf)

{

	if (bio->bi_opf & REQ_NOWAIT)

	if (bio_opf & REQ_NOWAIT)

		return dm_get_live_table_fast(md);

	else

		return dm_get_live_table(md, srcu_idx);

}



static inline void dm_put_live_table_bio(struct mapped_device *md, int srcu_idx,

					 struct bio *bio)

					 unsigned bio_opf)

{

	if (bio->bi_opf & REQ_NOWAIT)

	if (bio_opf & REQ_NOWAIT)

		dm_put_live_table_fast(md);

	else

		dm_put_live_table(md, srcu_idx);
@@ -1609,7 +1613,12 @@ static blk_status_t __split_and_process_bio(struct clone_info *ci) 
	ti = dm_table_find_target(ci->map, ci->sector);

	if (unlikely(!ti))

		return BLK_STS_IOERR;

	else if (unlikely(ci->is_abnormal_io))



	if (unlikely((ci->bio->bi_opf & REQ_NOWAIT) != 0) &&

	    unlikely(!dm_target_supports_nowait(ti->type)))

		return BLK_STS_NOTSUPP;



	if (unlikely(ci->is_abnormal_io))

		return __process_abnormal_io(ci, ti);



	/*
@@ -1711,8 +1720,9 @@ static void dm_submit_bio(struct bio *bio) 
	struct mapped_device *md = bio->bi_bdev->bd_disk->private_data;

	int srcu_idx;

	struct dm_table *map;

	unsigned bio_opf = bio->bi_opf;



	map = dm_get_live_table_bio(md, &srcu_idx, bio);

	map = dm_get_live_table_bio(md, &srcu_idx, bio_opf);



	/* If suspended, or map not yet available, queue this IO for later */

	if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) ||
@@ -1728,7 +1738,7 @@ static void dm_submit_bio(struct bio *bio) 


	dm_split_and_process_bio(md, map, bio);

out:

	dm_put_live_table_bio(md, srcu_idx, bio);

	dm_put_live_table_bio(md, srcu_idx, bio_opf);

}



static bool dm_poll_dm_io(struct dm_io *io, struct io_comp_batch *iob,