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 --- net/bluetooth/amp.c | 1 - net/bluetooth/smp.c | 1 - 2 files changed, 2 deletions(-) (limited to 'net/bluetooth') diff --git a/net/bluetooth/amp.c b/net/bluetooth/amp.c index 78bec8df8525..aaa39409eeb7 100644 --- a/net/bluetooth/amp.c +++ b/net/bluetooth/amp.c @@ -161,7 +161,6 @@ static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output) } shash->tfm = tfm; - shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP; ret = crypto_shash_digest(shash, plaintext, psize, output); diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index 621146d04c03..e68c715f8d37 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -183,7 +183,6 @@ static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, } desc->tfm = tfm; - desc->flags = 0; /* Swap key and message from LSB to MSB */ swap_buf(k, tmp, 16); -- cgit v1.2.3-59-g8ed1b