From: Mikulas Patocka Date: Tue, 7 Nov 2017 15:40:40 +0000 (-0500) Subject: dm integrity: allow unaligned bv_offset X-Git-Tag: v4.15-rc1~127^2~8 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=95b1369a9638cfa322ad1c0cde8efbe524059884;p=linux.git dm integrity: allow unaligned bv_offset When slub_debug is enabled kmalloc returns unaligned memory. XFS uses this unaligned memory for its buffers (if an unaligned buffer crosses a page, XFS frees it and allocates a full page instead - see the function xfs_buf_allocate_memory). dm-integrity checks if bv_offset is aligned on page size and this check fail with slub_debug and XFS. Fix this bug by removing the bv_offset check, leaving only the check for bv_len. Fixes: 7eada909bfd7 ("dm: add integrity target") Cc: stable@vger.kernel.org # v4.12+ Reported-by: Bruno Prémont Reviewed-by: Milan Broz Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 096fe9b66c50..5e6737a44468 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1376,7 +1376,7 @@ static int dm_integrity_map(struct dm_target *ti, struct bio *bio) struct bvec_iter iter; struct bio_vec bv; bio_for_each_segment(bv, bio, iter) { - if (unlikely((bv.bv_offset | bv.bv_len) & ((ic->sectors_per_block << SECTOR_SHIFT) - 1))) { + if (unlikely(bv.bv_len & ((ic->sectors_per_block << SECTOR_SHIFT) - 1))) { DMERR("Bio vector (%u,%u) is not aligned on %u-sector boundary", bv.bv_offset, bv.bv_len, ic->sectors_per_block); return DM_MAPIO_KILL;