4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Milan Broz gmazyland@gmail.com
commit 1856b9f7bcc8e9bdcccc360aabb56fbd4dd6c565 upstream.
The dm-crypt cipher specification in a mapping table is defined as: cipher[:keycount]-chainmode-ivmode[:ivopts] or (new crypt API format): capi:cipher_api_spec-ivmode[:ivopts]
For ESSIV, the parameter includes hash specification, for example: aes-cbc-essiv:sha256
The implementation expected that additional IV option to never include another dash '-' character.
But, with SHA3, there are names like sha3-256; so the mapping table parser fails:
dmsetup create test --table "0 8 crypt aes-cbc-essiv:sha3-256 9c1185a5c5e9fc54612808977ee8f5b9e 0 /dev/sdb 0" or (new crypt API format) dmsetup create test --table "0 8 crypt capi:cbc(aes)-essiv:sha3-256 9c1185a5c5e9fc54612808977ee8f5b9e 0 /dev/sdb 0"
device-mapper: crypt: Ignoring unexpected additional cipher options device-mapper: table: 253:0: crypt: Error creating IV device-mapper: ioctl: error adding target to table
Fix the dm-crypt constructor to ignore additional dash in IV options and also remove a bogus warning (that is ignored anyway).
Cc: stable@vger.kernel.org # 4.12+ Signed-off-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 | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)
--- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2405,9 +2405,21 @@ static int crypt_ctr_cipher_new(struct d * capi:cipher_api_spec-iv:ivopts */ tmp = &cipher_in[strlen("capi:")]; - cipher_api = strsep(&tmp, "-"); - *ivmode = strsep(&tmp, ":"); - *ivopts = tmp; + + /* Separate IV options if present, it can contain another '-' in hash name */ + *ivopts = strrchr(tmp, ':'); + if (*ivopts) { + **ivopts = '\0'; + (*ivopts)++; + } + /* Parse IV mode */ + *ivmode = strrchr(tmp, '-'); + if (*ivmode) { + **ivmode = '\0'; + (*ivmode)++; + } + /* The rest is crypto API spec */ + cipher_api = tmp;
if (*ivmode && !strcmp(*ivmode, "lmk")) cc->tfms_count = 64; @@ -2477,11 +2489,8 @@ static int crypt_ctr_cipher_old(struct d goto bad_mem;
chainmode = strsep(&tmp, "-"); - *ivopts = strsep(&tmp, "-"); - *ivmode = strsep(&*ivopts, ":"); - - if (tmp) - DMWARN("Ignoring unexpected additional cipher options"); + *ivmode = strsep(&tmp, ":"); + *ivopts = tmp;
/* * For compatibility with the original dm-crypt mapping format, if