From f7d76e05d058b832b373237566cc1af8251371b5 Mon Sep 17 00:00:00 2001 From: Corentin Labbe Date: Thu, 29 Nov 2018 14:42:21 +0000 Subject: crypto: user - fix use_after_free of struct xxx_request All crypto_stats functions use the struct xxx_request for feeding stats, but in some case this structure could already be freed. For fixing this, the needed parameters (len and alg) will be stored before the request being executed. Fixes: cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") Reported-by: syzbot Signed-off-by: Corentin Labbe Signed-off-by: Herbert Xu --- include/crypto/hash.h | 32 +++++--------------------------- 1 file changed, 5 insertions(+), 27 deletions(-) (limited to 'include/crypto/hash.h') diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 52920bed05ba..3b31c1b349ae 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -412,32 +412,6 @@ static inline void *ahash_request_ctx(struct ahash_request *req) int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, unsigned int keylen); -static inline void crypto_stat_ahash_update(struct ahash_request *req, int ret) -{ -#ifdef CONFIG_CRYPTO_STATS - struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); - - if (ret && ret != -EINPROGRESS && ret != -EBUSY) - atomic64_inc(&tfm->base.__crt_alg->hash_err_cnt); - else - atomic64_add(req->nbytes, &tfm->base.__crt_alg->hash_tlen); -#endif -} - -static inline void crypto_stat_ahash_final(struct ahash_request *req, int ret) -{ -#ifdef CONFIG_CRYPTO_STATS - struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); - - if (ret && ret != -EINPROGRESS && ret != -EBUSY) { - atomic64_inc(&tfm->base.__crt_alg->hash_err_cnt); - } else { - atomic64_inc(&tfm->base.__crt_alg->hash_cnt); - atomic64_add(req->nbytes, &tfm->base.__crt_alg->hash_tlen); - } -#endif -} - /** * crypto_ahash_finup() - update and finalize message digest * @req: reference to the ahash_request handle that holds all information @@ -552,10 +526,14 @@ static inline int crypto_ahash_init(struct ahash_request *req) */ static inline int crypto_ahash_update(struct ahash_request *req) { + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); + struct crypto_alg *alg = tfm->base.__crt_alg; + unsigned int nbytes = req->nbytes; int ret; + crypto_stats_get(alg); ret = crypto_ahash_reqtfm(req)->update(req); - crypto_stat_ahash_update(req, ret); + crypto_stats_ahash_update(nbytes, ret, alg); return ret; } -- cgit v1.2.3