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/algif_aead.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/algif_aead.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c index e2068b78..805f485d 100644 --- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -283,12 +283,23 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) { /* AIO operation */ + sock_hold(sk); areq->iocb = msg->msg_iocb; aead_request_set_callback(&areq->cra_u.aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, af_alg_async_cb, areq); err = ctx->enc ? crypto_aead_encrypt(&areq->cra_u.aead_req) : crypto_aead_decrypt(&areq->cra_u.aead_req); + + /* AIO operation in progress */ + if (err == -EINPROGRESS || err == -EBUSY) { + /* Remember output size that will be generated. */ + areq->outlen = outlen; + + return -EIOCBQUEUED; + } + + sock_put(sk); } else { /* Synchronous operation */ aead_request_set_callback(&areq->cra_u.aead_req, @@ -300,19 +311,9 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, &ctx->wait); } - /* AIO operation in progress */ - if (err == -EINPROGRESS) { - sock_hold(sk); - - /* Remember output size that will be generated. */ - areq->outlen = outlen; - - return -EIOCBQUEUED; - } free: - af_alg_free_areq_sgls(areq); - sock_kfree_s(sk, areq, areq->areqlen); + af_alg_free_resources(areq); return err ? err : outlen; } |