If the algorithm passed a zero statesize, do not pass a valid pointer into the export/import functions. Passing a valid pointer covers up bugs in driver code which then go on to smash the kernel stack. Instead, pass NULL, which will cause any attempt to write to the pointer to fail. Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> --- crypto/ahash.c | 3 ++- crypto/shash.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/crypto/ahash.c b/crypto/ahash.c index 8acb886032ae..9c1dc8d6106a 100644 --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -544,7 +544,8 @@ static int ahash_prepare_alg(struct ahash_alg *alg) struct crypto_alg *base = &alg->halg.base; if (alg->halg.digestsize > PAGE_SIZE / 8 || - alg->halg.statesize > PAGE_SIZE / 8) + alg->halg.statesize > PAGE_SIZE / 8 || + alg->halg.statesize == 0) return -EINVAL; base->cra_type = &crypto_ahash_type; diff --git a/crypto/shash.c b/crypto/shash.c index ecb1e3d39bf0..ab3384b38542 100644 --- a/crypto/shash.c +++ b/crypto/shash.c @@ -585,7 +585,8 @@ static int shash_prepare_alg(struct shash_alg *alg) if (alg->digestsize > PAGE_SIZE / 8 || alg->descsize > PAGE_SIZE / 8 || - alg->statesize > PAGE_SIZE / 8) + alg->statesize > PAGE_SIZE / 8 || + alg->statesize == 0) return -EINVAL; base->cra_type = &crypto_shash_type; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html