diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2015-12-06 02:51:37 +0100 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2015-12-09 20:16:22 +0800 |
| commit | 70d906bc17500edfa9bdd8c8b7e59618c7911613 (patch) | |
| tree | 0f7b5b7b5528cad419ffc19a3d29a82d61ae2935 /crypto | |
| parent | 79960943fdc114fd4583c9ab164b5c89da7aa601 (diff) | |
| download | linux-70d906bc17500edfa9bdd8c8b7e59618c7911613.tar.gz | |
crypto: skcipher - Copy iv from desc even for 0-len walks
Some ciphers actually support encrypting zero length plaintexts. For example, many AEAD modes support this. The resulting ciphertext for those winds up being only the authentication tag, which is a result of the key, the iv, the additional data, and the fact that the plaintext had zero length. The blkcipher constructors won't copy the IV to the right place, however, when using a zero length input, resulting in some significant problems when ciphers call their initialization routines, only to find that the ->iv parameter is uninitialized. One such example of this would be using chacha20poly1305 with a zero length input, which then calls chacha20, which calls the key setup routine, which eventually OOPSes due to the uninitialized ->iv member. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/ablkcipher.c | 2 | ||||
| -rw-r--r-- | crypto/blkcipher.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c index b4ffc5be1a93..e5b5721809e2 100644 --- a/crypto/ablkcipher.c +++ b/crypto/ablkcipher.c @@ -277,12 +277,12 @@ static int ablkcipher_walk_first(struct ablkcipher_request *req, if (WARN_ON_ONCE(in_irq())) return -EDEADLK; + walk->iv = req->info; walk->nbytes = walk->total; if (unlikely(!walk->total)) return 0; walk->iv_buffer = NULL; - walk->iv = req->info; if (unlikely(((unsigned long)walk->iv & alignmask))) { int err = ablkcipher_copy_iv(walk, tfm, alignmask); diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c index 11b981492031..8cc1622b2ee0 100644 --- a/crypto/blkcipher.c +++ b/crypto/blkcipher.c @@ -326,12 +326,12 @@ static int blkcipher_walk_first(struct blkcipher_desc *desc, if (WARN_ON_ONCE(in_irq())) return -EDEADLK; + walk->iv = desc->info; walk->nbytes = walk->total; if (unlikely(!walk->total)) return 0; walk->buffer = NULL; - walk->iv = desc->info; if (unlikely(((unsigned long)walk->iv & walk->alignmask))) { int err = blkcipher_copy_iv(walk); if (err) |