diff options
author | Stephan Mueller <smueller@chronox.de> | 2017-11-10 13:20:55 +0100 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-11-24 13:23:39 +0800 |
commit | 6ec9772926980159900fbc90d388566a245b2222 (patch) | |
tree | 777e7bfcaa778d04dd65182afd6b134549b4d8c8 /crypto/af_alg.c | |
parent | 8915d9a9e39646d11ddcbcacf32a0b42829422d7 (diff) | |
download | linux-crypto-6ec9772926980159900fbc90d388566a245b2222.tar.gz linux-crypto-6ec9772926980159900fbc90d388566a245b2222.zip |
crypto: af_alg - remove locking in async callback
The code paths protected by the socket-lock do not use or modify the
socket in a non-atomic fashion. The actions pertaining the socket do not
even need to be handled as an atomic operation. Thus, the socket-lock
can be safely ignored.
This fixes a bug regarding scheduling in atomic as the callback function
may be invoked in interrupt context.
In addition, the sock_hold is moved before the AIO encrypt/decrypt
operation to ensure that the socket is always present. This avoids a
tiny race window where the socket is unprotected and yet used by the AIO
operation.
Finally, the release of resources for a crypto operation is moved into a
common function of af_alg_free_resources.
Cc: <stable@vger.kernel.org>
Fixes: 8a15a4bf19477 ("crypto: algif_skcipher - overhaul memory management")
Fixes: 0c2a2d0aa6e4c ("crypto: algif_aead - overhaul memory management")
Reported-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Tested-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to '')
-rw-r--r-- | crypto/af_alg.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 85cea9de..358749c3 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -1021,6 +1021,18 @@ unlock: EXPORT_SYMBOL_GPL(af_alg_sendpage); /** + * af_alg_free_resources - release resources required for crypto request + */ +void af_alg_free_resources(struct af_alg_async_req *areq) +{ + struct sock *sk = areq->sk; + + af_alg_free_areq_sgls(areq); + sock_kfree_s(sk, areq, areq->areqlen); +} +EXPORT_SYMBOL_GPL(af_alg_free_resources); + +/** * af_alg_async_cb - AIO callback handler * * This handler cleans up the struct af_alg_async_req upon completion of the @@ -1036,18 +1048,13 @@ void af_alg_async_cb(struct crypto_async_request *_req, int err) struct kiocb *iocb = areq->iocb; unsigned int resultlen; - lock_sock(sk); - /* Buffer size written by crypto operation. */ resultlen = areq->outlen; - af_alg_free_areq_sgls(areq); - sock_kfree_s(sk, areq, areq->areqlen); - __sock_put(sk); + af_alg_free_resources(areq); + sock_put(sk); iocb->ki_complete(iocb, err ? err : resultlen, 0); - - release_sock(sk); } EXPORT_SYMBOL_GPL(af_alg_async_cb); |