path: root/net/bluetooth/smp.c
diff options
authorEric Biggers <ebiggers@google.com>2019-04-14 17:37:09 -0700
committerHerbert Xu <herbert@gondor.apana.org.au>2019-04-25 15:38:12 +0800
commit877b5691f27a1aec0d9b53095a323e45c30069e2 (patch)
tree59eba93e8d253fb0e12a0a2040de99e96e873933 /net/bluetooth/smp.c
parentcrypto: nx - don't abuse shash MAY_SLEEP flag (diff)
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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'net/bluetooth/smp.c')
1 files changed, 0 insertions, 1 deletions
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);