This is a note to let you know that I've just added the patch titled
dm integrity: allow unaligned bv_offset
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: dm-integrity-allow-unaligned-bv_offset.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 95b1369a9638cfa322ad1c0cde8efbe524059884 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka mpatocka@redhat.com Date: Tue, 7 Nov 2017 10:40:40 -0500 Subject: dm integrity: allow unaligned bv_offset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
From: Mikulas Patocka mpatocka@redhat.com
commit 95b1369a9638cfa322ad1c0cde8efbe524059884 upstream.
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") Reported-by: Bruno Prémont bonbons@sysophe.eu Reviewed-by: Milan Broz gmazyland@gmail.com Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/md/dm-integrity.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1376,7 +1376,7 @@ static int dm_integrity_map(struct dm_ta 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;
Patches currently in stable-queue which might be from mpatocka@redhat.com are
queue-4.14/dm-allocate-struct-mapped_device-with-kvzalloc.patch queue-4.14/dm-integrity-allow-unaligned-bv_offset.patch queue-4.14/dm-crypt-allow-unaligned-bv_offset.patch