diff options
| author | Marcelo Cerri <marcelo.cerri@canonical.com> | 2016-09-28 13:42:10 -0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2016-10-02 22:26:42 +0800 |
| commit | 80da44c29d997e28c4442825f35f4ac339813877 (patch) | |
| tree | 07d05485c86275960e270a968ded8baded310d2a | |
| parent | a397ba829d7f8aff4c90af3704573a28ccd61a59 (diff) | |
crypto: vmx - Fix memory corruption caused by p8_ghash
This patch changes the p8_ghash driver to use ghash-generic as a fixed
fallback implementation. This allows the correct value of descsize to be
defined directly in its shash_alg structure and avoids problems with
incorrect buffer sizes when its state is exported or imported.
Reported-by: Jan Stancek <jstancek@redhat.com>
Fixes: cc333cd68dfa ("crypto: vmx - Adding GHASH routines for VMX module")
Cc: stable@vger.kernel.org
Signed-off-by: Marcelo Cerri <marcelo.cerri@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
| -rw-r--r-- | drivers/crypto/vmx/ghash.c | 31 |
1 files changed, 16 insertions, 15 deletions
diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c index 6c999cb01b80..27a94a119009 100644 --- a/drivers/crypto/vmx/ghash.c +++ b/drivers/crypto/vmx/ghash.c @@ -26,16 +26,13 @@ #include <linux/hardirq.h> #include <asm/switch_to.h> #include <crypto/aes.h> +#include <crypto/ghash.h> #include <crypto/scatterwalk.h> #include <crypto/internal/hash.h> #include <crypto/b128ops.h> #define IN_INTERRUPT in_interrupt() -#define GHASH_BLOCK_SIZE (16) -#define GHASH_DIGEST_SIZE (16) -#define GHASH_KEY_LEN (16) - void gcm_init_p8(u128 htable[16], const u64 Xi[2]); void gcm_gmult_p8(u64 Xi[2], const u128 htable[16]); void gcm_ghash_p8(u64 Xi[2], const u128 htable[16], @@ -55,16 +52,11 @@ struct p8_ghash_desc_ctx { static int p8_ghash_init_tfm(struct crypto_tfm *tfm) { - const char *alg; + const char *alg = "ghash-generic"; struct crypto_shash *fallback; struct crypto_shash *shash_tfm = __crypto_shash_cast(tfm); struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm); - if (!(alg = crypto_tfm_alg_name(tfm))) { - printk(KERN_ERR "Failed to get algorithm name.\n"); - return -ENOENT; - } - fallback = crypto_alloc_shash(alg, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(fallback)) { printk(KERN_ERR @@ -78,10 +70,18 @@ static int p8_ghash_init_tfm(struct crypto_tfm *tfm) crypto_shash_set_flags(fallback, crypto_shash_get_flags((struct crypto_shash *) tfm)); - ctx->fallback = fallback; - shash_tfm->descsize = sizeof(struct p8_ghash_desc_ctx) - + crypto_shash_descsize(fallback); + /* Check if the descsize defined in the algorithm is still enough. */ + if (shash_tfm->descsize < sizeof(struct p8_ghash_desc_ctx) + + crypto_shash_descsize(fallback)) { + printk(KERN_ERR + "Desc size of the fallback implementation (%s) does not match the expected value: %lu vs %u\n", + alg, + shash_tfm->descsize - sizeof(struct p8_ghash_desc_ctx), + crypto_shash_descsize(fallback)); + return -EINVAL; + } + ctx->fallback = fallback; return 0; } @@ -113,7 +113,7 @@ static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key, { struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(tfm)); - if (keylen != GHASH_KEY_LEN) + if (keylen != GHASH_BLOCK_SIZE) return -EINVAL; preempt_disable(); @@ -211,7 +211,8 @@ struct shash_alg p8_ghash_alg = { .update = p8_ghash_update, .final = p8_ghash_final, .setkey = p8_ghash_setkey, - .descsize = sizeof(struct p8_ghash_desc_ctx), + .descsize = sizeof(struct p8_ghash_desc_ctx) + + sizeof(struct ghash_desc_ctx), .base = { .cra_name = "ghash", .cra_driver_name = "p8_ghash", |