Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - fix chacha20 crash on zero-length input due to unset IV

   - fix potential race conditions in mcryptd with spinlock

   - only wait once at top of algif recvmsg to avoid inconsistencies

   - fix potential use-after-free in algif_aead/algif_skcipher"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: af_alg - fix race accessing cipher request
  crypto: mcryptd - protect the per-CPU queue with a lock
  crypto: af_alg - wait for data at beginning of recvmsg
  crypto: skcipher - set walk.iv for zero-length inputs

6 files changed, 37 insertions, 35 deletions

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 415a54ced4d6..444a387df219 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -1138,12 +1138,6 @@ int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags,
                 if (!af_alg_readable(sk))
                         break;
 
-                if (!ctx->used) {
-                        err = af_alg_wait_for_data(sk, flags);
-                        if (err)
-                                return err;
-                }
-
                 seglen = min_t(size_t, (maxsize - len),
                                msg_data_left(msg));
 
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index 48b34e9c6834..ddcc45f77edd 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -111,6 +111,12 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
         size_t usedpages = 0;           /* [in]  RX bufs to be used from user */
         size_t processed = 0;           /* [in]  TX bufs to be consumed */
 
+        if (!ctx->used) {
+                err = af_alg_wait_for_data(sk, flags);
+                if (err)
+                        return err;
+        }
+
         /*
          * Data length provided by caller via sendmsg/sendpage that has not
          * yet been processed.
@@ -285,6 +291,10 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
                 /* AIO operation */
                 sock_hold(sk);
                 areq->iocb = msg->msg_iocb;
+
+                /* Remember output size that will be generated. */
+                areq->outlen = outlen;
+
                 aead_request_set_callback(&areq->cra_u.aead_req,
                                           CRYPTO_TFM_REQ_MAY_BACKLOG,
                                           af_alg_async_cb, areq);
@@ -292,12 +302,8 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg,
                                  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;
-
+                if (err == -EINPROGRESS || err == -EBUSY)
                         return -EIOCBQUEUED;
-                }
 
                 sock_put(sk);
         } else {
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 30cff827dd8f..baef9bfccdda 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -72,6 +72,12 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
         int err = 0;
         size_t len = 0;
 
+        if (!ctx->used) {
+                err = af_alg_wait_for_data(sk, flags);
+                if (err)
+                        return err;
+        }
+
         /* Allocate cipher request for current operation. */
         areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) +
                                      crypto_skcipher_reqsize(tfm));
@@ -119,6 +125,10 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
                 /* AIO operation */
                 sock_hold(sk);
                 areq->iocb = msg->msg_iocb;
+
+                /* Remember output size that will be generated. */
+                areq->outlen = len;
+
                 skcipher_request_set_callback(&areq->cra_u.skcipher_req,
                                               CRYPTO_TFM_REQ_MAY_SLEEP,
                                               af_alg_async_cb, areq);
@@ -127,12 +137,8 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
                         crypto_skcipher_decrypt(&areq->cra_u.skcipher_req);
 
                 /* AIO operation in progress */
-                if (err == -EINPROGRESS || err == -EBUSY) {
-                        /* Remember output size that will be generated. */
-                        areq->outlen = len;
-
+                if (err == -EINPROGRESS || err == -EBUSY)
                         return -EIOCBQUEUED;
-                }
 
                 sock_put(sk);
         } else {
diff --git a/crypto/mcryptd.c b/crypto/mcryptd.c
index 4e6472658852..eca04d3729b3 100644
--- a/crypto/mcryptd.c
+++ b/crypto/mcryptd.c
@@ -81,6 +81,7 @@ static int mcryptd_init_queue(struct mcryptd_queue *queue,
                 pr_debug("cpu_queue #%d %p\n", cpu, queue->cpu_queue);
                 crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
                 INIT_WORK(&cpu_queue->work, mcryptd_queue_worker);
+                spin_lock_init(&cpu_queue->q_lock);
         }
         return 0;
 }
@@ -104,15 +105,16 @@ static int mcryptd_enqueue_request(struct mcryptd_queue *queue,
         int cpu, err;
         struct mcryptd_cpu_queue *cpu_queue;
 
-        cpu = get_cpu();
-        cpu_queue = this_cpu_ptr(queue->cpu_queue);
-        rctx->tag.cpu = cpu;
+        cpu_queue = raw_cpu_ptr(queue->cpu_queue);
+        spin_lock(&cpu_queue->q_lock);
+        cpu = smp_processor_id();
+        rctx->tag.cpu = smp_processor_id();
 
         err = crypto_enqueue_request(&cpu_queue->queue, request);
         pr_debug("enqueue request: cpu %d cpu_queue %p request %p\n",
                  cpu, cpu_queue, request);
+        spin_unlock(&cpu_queue->q_lock);
         queue_work_on(cpu, kcrypto_wq, &cpu_queue->work);
-        put_cpu();
 
         return err;
 }
@@ -161,16 +163,11 @@ static void mcryptd_queue_worker(struct work_struct *work)
         cpu_queue = container_of(work, struct mcryptd_cpu_queue, work);
         i = 0;
         while (i < MCRYPTD_BATCH || single_task_running()) {
-                /*
-                 * preempt_disable/enable is used to prevent
-                 * being preempted by mcryptd_enqueue_request()
-                 */
-                local_bh_disable();
-                preempt_disable();
+
+                spin_lock_bh(&cpu_queue->q_lock);
                 backlog = crypto_get_backlog(&cpu_queue->queue);
                 req = crypto_dequeue_request(&cpu_queue->queue);
-                preempt_enable();
-                local_bh_enable();
+                spin_unlock_bh(&cpu_queue->q_lock);
 
                 if (!req) {
                         mcryptd_opportunistic_flush();
@@ -185,7 +182,7 @@ static void mcryptd_queue_worker(struct work_struct *work)
                 ++i;
         }
         if (cpu_queue->queue.qlen)
-                queue_work(kcrypto_wq, &cpu_queue->work);
+                queue_work_on(smp_processor_id(), kcrypto_wq, &cpu_queue->work);
 }
 
 void mcryptd_flusher(struct work_struct *__work)
diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 778e0ff42bfa..11af5fd6a443 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c
@@ -449,6 +449,8 @@ static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 
         walk->total = req->cryptlen;
         walk->nbytes = 0;
+        walk->iv = req->iv;
+        walk->oiv = req->iv;
 
         if (unlikely(!walk->total))
                 return 0;
@@ -456,9 +458,6 @@ static int skcipher_walk_skcipher(struct skcipher_walk *walk,
         scatterwalk_start(&walk->in, req->src);
         scatterwalk_start(&walk->out, req->dst);
 
-        walk->iv = req->iv;
-        walk->oiv = req->iv;
-
         walk->flags &= ~SKCIPHER_WALK_SLEEP;
         walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
                        SKCIPHER_WALK_SLEEP : 0;
@@ -510,6 +509,8 @@ static int skcipher_walk_aead_common(struct skcipher_walk *walk,
         int err;
 
         walk->nbytes = 0;
+        walk->iv = req->iv;
+        walk->oiv = req->iv;
 
         if (unlikely(!walk->total))
                 return 0;
@@ -525,9 +526,6 @@ static int skcipher_walk_aead_common(struct skcipher_walk *walk,
         scatterwalk_done(&walk->in, 0, walk->total);
         scatterwalk_done(&walk->out, 0, walk->total);
 
-        walk->iv = req->iv;
-        walk->oiv = req->iv;
-
         if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
                 walk->flags |= SKCIPHER_WALK_SLEEP;
         else
diff --git a/include/crypto/mcryptd.h b/include/crypto/mcryptd.h
index cceafa01f907..b67404fc4b34 100644
--- a/include/crypto/mcryptd.h
+++ b/include/crypto/mcryptd.h
@@ -27,6 +27,7 @@ static inline struct mcryptd_ahash *__mcryptd_ahash_cast(
 
 struct mcryptd_cpu_queue {
         struct crypto_queue queue;
+        spinlock_t q_lock;
         struct work_struct work;
 };