Re: [PATCH v3 10/10] crypto: safexcel - zeroize crypto_aes_ctx with __cleanup(aes_zeroize_ctx)
Antoine Tenart <[email protected]>
| Newsgroups | org.kernel.vger.linux-crypto,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <anRC5AYai6TVHcac@kwain> |
On Wed, Aug 05, 2026 at 01:57:48PM +0200, Thomas Huth wrote: > From: Thomas Huth <[email protected]> > > The code clears the crypto_aes_ctx in most cases already with > memzero_explicit(), but safexcel_skcipher_aesxts_setkey() runs > aes_expandkey() twice, and in case the second call fails, the > context from the first call is leaked. > > To fix this issue and to avoid future similar problems, let's use > the new __cleanup(aes_zeroize_ctx) mechanism to make sure that we > always clear the crypto_aes_ctx in all cases. > > Signed-off-by: Thomas Huth <[email protected]> Acked-by: Antoine Tenart <[email protected]> > --- > drivers/crypto/inside-secure/safexcel_cipher.c | 13 ++++--------- > drivers/crypto/inside-secure/safexcel_hash.c | 3 +-- > 2 files changed, 5 insertions(+), 11 deletions(-) > > diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c > index e94686490bb27..50e8792b399de 100644 > --- a/drivers/crypto/inside-secure/safexcel_cipher.c > +++ b/drivers/crypto/inside-secure/safexcel_cipher.c > @@ -375,7 +375,7 @@ static int safexcel_skcipher_aes_setkey(struct crypto_skcipher *ctfm, > struct crypto_tfm *tfm = crypto_skcipher_tfm(ctfm); > struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); > struct safexcel_crypto_priv *priv = ctx->base.priv; > - struct crypto_aes_ctx aes; > + struct crypto_aes_ctx aes __cleanup(aes_zeroize_ctx); > int ret, i; > > ret = aes_expandkey(&aes, key, len); > @@ -396,7 +396,6 @@ static int safexcel_skcipher_aes_setkey(struct crypto_skcipher *ctfm, > > ctx->key_len = len; > > - memzero_explicit(&aes, sizeof(aes)); > return 0; > } > > @@ -1357,7 +1356,7 @@ static int safexcel_skcipher_aesctr_setkey(struct crypto_skcipher *ctfm, > struct crypto_tfm *tfm = crypto_skcipher_tfm(ctfm); > struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); > struct safexcel_crypto_priv *priv = ctx->base.priv; > - struct crypto_aes_ctx aes; > + struct crypto_aes_ctx aes __cleanup(aes_zeroize_ctx); > int ret, i; > unsigned int keylen; > > @@ -1383,7 +1382,6 @@ static int safexcel_skcipher_aesctr_setkey(struct crypto_skcipher *ctfm, > > ctx->key_len = keylen; > > - memzero_explicit(&aes, sizeof(aes)); > return 0; > } > > @@ -2537,7 +2535,7 @@ static int safexcel_skcipher_aesxts_setkey(struct crypto_skcipher *ctfm, > struct crypto_tfm *tfm = crypto_skcipher_tfm(ctfm); > struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); > struct safexcel_crypto_priv *priv = ctx->base.priv; > - struct crypto_aes_ctx aes; > + struct crypto_aes_ctx aes __cleanup(aes_zeroize_ctx); > int ret, i; > unsigned int keylen; > > @@ -2585,7 +2583,6 @@ static int safexcel_skcipher_aesxts_setkey(struct crypto_skcipher *ctfm, > > ctx->key_len = keylen << 1; > > - memzero_explicit(&aes, sizeof(aes)); > return 0; > } > > @@ -2751,12 +2748,11 @@ static int safexcel_aead_ccm_setkey(struct crypto_aead *ctfm, const u8 *key, > struct crypto_tfm *tfm = crypto_aead_tfm(ctfm); > struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); > struct safexcel_crypto_priv *priv = ctx->base.priv; > - struct crypto_aes_ctx aes; > + struct crypto_aes_ctx aes __cleanup(aes_zeroize_ctx); > int ret, i; > > ret = aes_expandkey(&aes, key, len); > if (ret) { > - memzero_explicit(&aes, sizeof(aes)); > return ret; > } > > @@ -2785,7 +2781,6 @@ static int safexcel_aead_ccm_setkey(struct crypto_aead *ctfm, const u8 *key, > else > ctx->hash_alg = CONTEXT_CONTROL_CRYPTO_ALG_XCBC128; > > - memzero_explicit(&aes, sizeof(aes)); > return 0; > } > > diff --git a/drivers/crypto/inside-secure/safexcel_hash.c b/drivers/crypto/inside-secure/safexcel_hash.c > index 3402e570d045c..20c17eb09495e 100644 > --- a/drivers/crypto/inside-secure/safexcel_hash.c > +++ b/drivers/crypto/inside-secure/safexcel_hash.c > @@ -1905,7 +1905,7 @@ static int safexcel_cbcmac_setkey(struct crypto_ahash *tfm, const u8 *key, > unsigned int len) > { > struct safexcel_ahash_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); > - struct crypto_aes_ctx aes; > + struct crypto_aes_ctx aes __cleanup(aes_zeroize_ctx); > int ret, i; > > ret = aes_expandkey(&aes, key, len); > @@ -1928,7 +1928,6 @@ static int safexcel_cbcmac_setkey(struct crypto_ahash *tfm, const u8 *key, > } > ctx->cbcmac = true; > > - memzero_explicit(&aes, sizeof(aes)); > return 0; > } > > -- > 2.55.0 >