From 877b5691f27a1aec0d9b53095a323e45c30069e2 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 14 Apr 2019 17:37:09 -0700 Subject: crypto: shash - remove shash_desc::flags The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- security/keys/dh.c | 1 - security/keys/encrypted-keys/encrypted.c | 1 - security/keys/trusted.c | 1 - 3 files changed, 3 deletions(-) (limited to 'security/keys') diff --git a/security/keys/dh.c b/security/keys/dh.c index 711e89d8c415..23f95dec771b 100644 --- a/security/keys/dh.c +++ b/security/keys/dh.c @@ -112,7 +112,6 @@ static int kdf_alloc(struct kdf_sdesc **sdesc_ret, char *hashname) if (!sdesc) goto out_free_tfm; sdesc->shash.tfm = tfm; - sdesc->shash.flags = 0x0; *sdesc_ret = sdesc; diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 347108f660a1..1b1456b21a93 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -333,7 +333,6 @@ static int calc_hash(struct crypto_shash *tfm, u8 *digest, int err; desc->tfm = tfm; - desc->flags = 0; err = crypto_shash_digest(desc, buf, buflen, digest); shash_desc_zero(desc); diff --git a/security/keys/trusted.c b/security/keys/trusted.c index bcc9c6ead7fd..45ffd9e53937 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -55,7 +55,6 @@ static struct sdesc *init_sdesc(struct crypto_shash *alg) if (!sdesc) return ERR_PTR(-ENOMEM); sdesc->shash.tfm = alg; - sdesc->shash.flags = 0x0; return sdesc; } -- cgit v1.2.3-55-g7522