This is a note to let you know that I've just added the patch titled
dm crypt: 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-crypt-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 0440d5c0ca9744b92a07aeb6df0a9a75db6f4280 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka mpatocka@redhat.com Date: Tue, 7 Nov 2017 10:35:57 -0500 Subject: dm crypt: 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 0440d5c0ca9744b92a07aeb6df0a9a75db6f4280 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-crypt checks if bv_offset is aligned on page size and these checks fail with slub_debug and XFS.
Fix this bug by removing the bv_offset checks. Switch to checking if bv_len is aligned instead of bv_offset (this check should be sufficient to prevent overruns if a bio with too small bv_len is received).
Fixes: 8f0009a22517 ("dm crypt: optionally support larger encryption sector size") Reported-by: Bruno Prémont bonbons@sysophe.eu Tested-by: Bruno Prémont bonbons@sysophe.eu Signed-off-by: Mikulas Patocka mpatocka@redhat.com Reviewed-by: Milan Broz gmazyland@gmail.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/md/dm-crypt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1075,7 +1075,7 @@ static int crypt_convert_block_aead(stru BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
/* Reject unexpected unaligned bio. */ - if (unlikely(bv_in.bv_offset & (cc->sector_size - 1))) + if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) return -EIO;
dmreq = dmreq_of_req(cc, req); @@ -1168,7 +1168,7 @@ static int crypt_convert_block_skcipher( int r = 0;
/* Reject unexpected unaligned bio. */ - if (unlikely(bv_in.bv_offset & (cc->sector_size - 1))) + if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) return -EIO;
dmreq = dmreq_of_req(cc, req);
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