From 69f1a9702d3f7d96f50cd05c733c3c43a5b19741 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 2 Mar 2021 21:33:03 +0100 Subject: [PATCH] crypto: api - check for ERR pointers in crypto_destroy_tfm() [ Upstream commit 83681f2bebb34dbb3f03fecd8f570308ab8b7c2c ] Given that crypto_alloc_tfm() may return ERR pointers, and to avoid crashes on obscure error paths where such pointers are presented to crypto_destroy_tfm() (such as [0]), add an ERR_PTR check there before dereferencing the second argument as a struct crypto_tfm pointer. [0] https://lore.kernel.org/linux-crypto/000000000000de949705bc59e0f6@google.com/ Reported-by: syzbot+12cf5fbfdeba210a89dd@syzkaller.appspotmail.com Reviewed-by: Eric Biggers Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- crypto/api.c | 2 +- include/crypto/acompress.h | 2 ++ include/crypto/aead.h | 2 ++ include/crypto/akcipher.h | 2 ++ include/crypto/hash.h | 4 ++++ include/crypto/kpp.h | 2 ++ include/crypto/rng.h | 2 ++ include/crypto/skcipher.h | 2 ++ 8 files changed, 17 insertions(+), 1 deletion(-) diff --git a/crypto/api.c b/crypto/api.c index eda0c56b8615..c71d1485541c 100644 --- a/crypto/api.c +++ b/crypto/api.c @@ -568,7 +568,7 @@ void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm) { struct crypto_alg *alg; - if (unlikely(!mem)) + if (IS_ERR_OR_NULL(mem)) return; alg = tfm->__crt_alg; diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h index d873f999b334..3a801a7d3a0e 100644 --- a/include/crypto/acompress.h +++ b/include/crypto/acompress.h @@ -147,6 +147,8 @@ static inline struct crypto_acomp *crypto_acomp_reqtfm(struct acomp_req *req) * crypto_free_acomp() -- free ACOMPRESS tfm handle * * @tfm: ACOMPRESS tfm handle allocated with crypto_alloc_acomp() + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_acomp(struct crypto_acomp *tfm) { diff --git a/include/crypto/aead.h b/include/crypto/aead.h index 3c245b1859e7..3b870b4e8275 100644 --- a/include/crypto/aead.h +++ b/include/crypto/aead.h @@ -179,6 +179,8 @@ static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm) /** * crypto_free_aead() - zeroize and free aead handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_aead(struct crypto_aead *tfm) { diff --git a/include/crypto/akcipher.h b/include/crypto/akcipher.h index 6924b091adec..8913b42fcb34 100644 --- a/include/crypto/akcipher.h +++ b/include/crypto/akcipher.h @@ -174,6 +174,8 @@ static inline struct crypto_akcipher *crypto_akcipher_reqtfm( * crypto_free_akcipher() - free AKCIPHER tfm handle * * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_akcipher(struct crypto_akcipher *tfm) { diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 84e9f2380edf..e993c6beec07 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -260,6 +260,8 @@ static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) /** * crypto_free_ahash() - zeroize and free the ahash handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_ahash(struct crypto_ahash *tfm) { @@ -703,6 +705,8 @@ static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) /** * crypto_free_shash() - zeroize and free the message digest handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_shash(struct crypto_shash *tfm) { diff --git a/include/crypto/kpp.h b/include/crypto/kpp.h index cd9a9b500624..19a2eadbef61 100644 --- a/include/crypto/kpp.h +++ b/include/crypto/kpp.h @@ -154,6 +154,8 @@ static inline void crypto_kpp_set_flags(struct crypto_kpp *tfm, u32 flags) * crypto_free_kpp() - free KPP tfm handle * * @tfm: KPP tfm handle allocated with crypto_alloc_kpp() + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_kpp(struct crypto_kpp *tfm) { diff --git a/include/crypto/rng.h b/include/crypto/rng.h index 8b4b844b4eef..17bb3673d3c1 100644 --- a/include/crypto/rng.h +++ b/include/crypto/rng.h @@ -111,6 +111,8 @@ static inline struct rng_alg *crypto_rng_alg(struct crypto_rng *tfm) /** * crypto_free_rng() - zeroize and free RNG handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_rng(struct crypto_rng *tfm) { diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h index aada87916918..0bce6005d325 100644 --- a/include/crypto/skcipher.h +++ b/include/crypto/skcipher.h @@ -203,6 +203,8 @@ static inline struct crypto_tfm *crypto_skcipher_tfm( /** * crypto_free_skcipher() - zeroize and free cipher handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_skcipher(struct crypto_skcipher *tfm) {