From: Nikos Tsironis ntsironis@arrikto.com
[ Upstream commit 9fc06ff56845cc5ccafec52f545fc2e08d22f849 ]
Add missing casts when converting from regions to sectors.
In case BITS_PER_LONG == 32, the lack of the appropriate casts can lead to overflows and miscalculation of the device sector.
As a result, we could end up discarding and/or copying the wrong parts of the device, thus corrupting the device's data.
Fixes: 7431b7835f55 ("dm: add clone target") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Nikos Tsironis ntsironis@arrikto.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-clone-target.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/md/dm-clone-target.c b/drivers/md/dm-clone-target.c index 315d3bca59792..eb7a5d3ba81a2 100644 --- a/drivers/md/dm-clone-target.c +++ b/drivers/md/dm-clone-target.c @@ -282,7 +282,7 @@ static bool bio_triggers_commit(struct clone *clone, struct bio *bio) /* Get the address of the region in sectors */ static inline sector_t region_to_sector(struct clone *clone, unsigned long region_nr) { - return (region_nr << clone->region_shift); + return ((sector_t)region_nr << clone->region_shift); }
/* Get the region number of the bio */ @@ -471,7 +471,7 @@ static void complete_discard_bio(struct clone *clone, struct bio *bio, bool succ if (test_bit(DM_CLONE_DISCARD_PASSDOWN, &clone->flags) && success) { remap_to_dest(clone, bio); bio_region_range(clone, bio, &rs, &nr_regions); - trim_bio(bio, rs << clone->region_shift, + trim_bio(bio, region_to_sector(clone, rs), nr_regions << clone->region_shift); generic_make_request(bio); } else @@ -798,11 +798,14 @@ static void hydration_copy(struct dm_clone_region_hydration *hd, unsigned int nr struct dm_io_region from, to; struct clone *clone = hd->clone;
+ if (WARN_ON(!nr_regions)) + return; + region_size = clone->region_size; region_start = hd->region_nr; region_end = region_start + nr_regions - 1;
- total_size = (nr_regions - 1) << clone->region_shift; + total_size = region_to_sector(clone, nr_regions - 1);
if (region_end == clone->nr_regions - 1) { /*