diff options
author | Eric Biggers <ebiggers@google.com> | 2019-04-15 02:37:09 +0200 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2019-04-25 09:38:12 +0200 |
commit | 877b5691f27a1aec0d9b53095a323e45c30069e2 (patch) | |
tree | 59eba93e8d253fb0e12a0a2040de99e96e873933 /net/sctp | |
parent | crypto: nx - don't abuse shash MAY_SLEEP flag (diff) | |
download | linux-877b5691f27a1aec0d9b53095a323e45c30069e2.tar.xz linux-877b5691f27a1aec0d9b53095a323e45c30069e2.zip |
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/sctp')
-rw-r--r-- | net/sctp/auth.c | 1 | ||||
-rw-r--r-- | net/sctp/sm_make_chunk.c | 2 |
2 files changed, 0 insertions, 3 deletions
diff --git a/net/sctp/auth.c b/net/sctp/auth.c index 39d72e58b8e5..31569f4809f6 100644 --- a/net/sctp/auth.c +++ b/net/sctp/auth.c @@ -760,7 +760,6 @@ void sctp_auth_calculate_hmac(const struct sctp_association *asoc, SHASH_DESC_ON_STACK(desc, tfm); desc->tfm = tfm; - desc->flags = 0; crypto_shash_digest(desc, (u8 *)auth, end - (unsigned char *)auth, digest); shash_desc_zero(desc); diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index d05c57664e36..72e74503f9fc 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -1684,7 +1684,6 @@ static struct sctp_cookie_param *sctp_pack_cookie( /* Sign the message. */ desc->tfm = sctp_sk(ep->base.sk)->hmac; - desc->flags = 0; err = crypto_shash_setkey(desc->tfm, ep->secret_key, sizeof(ep->secret_key)) ?: @@ -1755,7 +1754,6 @@ struct sctp_association *sctp_unpack_cookie( int err; desc->tfm = sctp_sk(ep->base.sk)->hmac; - desc->flags = 0; err = crypto_shash_setkey(desc->tfm, ep->secret_key, sizeof(ep->secret_key)) ?: |