lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 22 Sep 2016 19:40:47 +0200 From: Greg Kroah-Hartman <gregkh@...uxfoundation.org> To: linux-kernel@...r.kernel.org Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, stable@...r.kernel.org, Mikulas Patocka <mpatocka@...hat.com>, Mike Snitzer <snitzer@...hat.com> Subject: [PATCH 4.7 113/184] dm crypt: fix error with too large bios 4.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka <mpatocka@...hat.com> commit 4e870e948fbabf62b78e8410f04c67703e7c816b upstream. When dm-crypt processes writes, it allocates a new bio in crypt_alloc_buffer(). The bio is allocated from a bio set and it can have at most BIO_MAX_PAGES vector entries, however the incoming bio can be larger (e.g. if it was allocated by bcache). If the incoming bio is larger, bio_alloc_bioset() fails and an error is returned. To avoid the error, we test for a too large bio in the function crypt_map() and use dm_accept_partial_bio() to split the bio. dm_accept_partial_bio() trims the current bio to the desired size and asks DM core to send another bio with the rest of the data. Signed-off-by: Mikulas Patocka <mpatocka@...hat.com> Signed-off-by: Mike Snitzer <snitzer@...hat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org> --- drivers/md/dm-crypt.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1923,6 +1923,13 @@ static int crypt_map(struct dm_target *t return DM_MAPIO_REMAPPED; } + /* + * Check if bio is too large, split as needed. + */ + if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) && + bio_data_dir(bio) == WRITE) + dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT)); + io = dm_per_bio_data(bio, cc->per_bio_data_size); crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); io->ctx.req = (struct skcipher_request *)(io + 1);
Powered by blists - more mailing lists