[PATCH] crypto: algif_aead - Only wake up when ctx->more is zero

[Herbert Xu]

AEAD does not support partial requests so we must not wake up
while ctx->more is set.  While we're fixing this also change
algif_skcipher to only wake up when at least a block is available
as otherwise we'd just fail straight away with -EINVAL.

Fixes: 2d97591ef43d ("crypto: af_alg - consolidation of...")
Signed-off-by: Herbert Xu <herb...@gondor.apana.org.au>

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index b1cd3535c5256..474a9511f0ed4 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -738,9 +738,10 @@ EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
  *
  * @sk socket of connection to user space
  * @flags If MSG_DONTWAIT is set, then only report if function would sleep
+ * @min Set to minimum request size if partial requests are allowed.
  * @return 0 when writable memory is available, < 0 upon error
  */
-int af_alg_wait_for_data(struct sock *sk, unsigned flags)
+int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min)
 {
        DEFINE_WAIT_FUNC(wait, woken_wake_function);
        struct alg_sock *ask = alg_sk(sk);
@@ -758,7 +759,8 @@ int af_alg_wait_for_data(struct sock *sk, unsigned flags)
                if (signal_pending(current))
                        break;
                timeout = MAX_SCHEDULE_TIMEOUT;
-               if (sk_wait_event(sk, &timeout, (ctx->used || !ctx->more),
+               if (sk_wait_event(sk, &timeout,
+                                 (min && ctx->used >= min) || !ctx->more,
                                  &wait)) {
                        err = 0;
                        break;
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index eb1910b6d434c..efea00046be65 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -107,7 +107,7 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr 
*msg,
        size_t processed = 0;           /* [in]  TX bufs to be consumed */
 
        if (!ctx->used) {
-               err = af_alg_wait_for_data(sk, flags);
+               err = af_alg_wait_for_data(sk, flags, 0);
                if (err)
                        return err;
        }
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 24dd2fc2431cc..5b334fd9432c0 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -62,7 +62,7 @@ static int _skcipher_recvmsg(struct socket *sock, struct 
msghdr *msg,
        size_t len = 0;
 
        if (!ctx->used) {
-               err = af_alg_wait_for_data(sk, flags);
+               err = af_alg_wait_for_data(sk, flags, bs);
                if (err)
                        return err;
        }
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 56527c85d1222..e1e5525473e4c 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -226,7 +226,7 @@ unsigned int af_alg_count_tsgl(struct sock *sk, size_t 
bytes, size_t offset);
 void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst,
                      size_t dst_offset);
 void af_alg_wmem_wakeup(struct sock *sk);
-int af_alg_wait_for_data(struct sock *sk, unsigned flags);
+int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min);
 int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
                   unsigned int ivsize);
 ssize_t af_alg_sendpage(struct socket *sock, struct page *page,
-- 
Email: Herbert Xu <herb...@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt