From 27c7003697fc2c78f965984aa224ef26cd6b2949 Mon Sep 17 00:00:00 2001 From: Milan Broz Date: Wed, 3 Jan 2018 22:48:59 +0100 Subject: [PATCH] dm crypt: fix crash by adding missing check for auth key size If dm-crypt uses authenticated mode with separate MAC, there are two concatenated part of the key structure - key(s) for encryption and authentication key. Add a missing check for authenticated key length. If this key length is smaller than actually provided key, dm-crypt now properly fails instead of crashing. Fixes: ef43aa3806 ("dm crypt: add cryptographic data integrity protection (authenticated encryption)") Cc: stable@vger.kernel.org # 4.12+ Reported-by: Salah Coronya Signed-off-by: Milan Broz Signed-off-by: Mike Snitzer --- drivers/md/dm-crypt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 9fc12f556534..4cc3809b2a3a 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1954,10 +1954,15 @@ static int crypt_setkey(struct crypt_config *cc) /* Ignore extra keys (which are used for IV etc) */ subkey_size = crypt_subkey_size(cc); - if (crypt_integrity_hmac(cc)) + if (crypt_integrity_hmac(cc)) { + if (subkey_size < cc->key_mac_size) + return -EINVAL; + crypt_copy_authenckey(cc->authenc_key, cc->key, subkey_size - cc->key_mac_size, cc->key_mac_size); + } + for (i = 0; i < cc->tfms_count; i++) { if (crypt_integrity_hmac(cc)) r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],