diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 68cc9290cabe9a9f8a264908466897f2f93e039d..dbddcf52b9920ff66a17e524d0f084c254dc836f 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -969,6 +969,12 @@ int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	}
 
 	lock_sock(sk);
+	if (ctx->write) {
+		release_sock(sk);
+		return -EBUSY;
+	}
+	ctx->write = true;
+
 	if (ctx->init && !ctx->more) {
 		if (ctx->used) {
 			err = -EINVAL;
@@ -1103,6 +1109,7 @@ int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
 
 unlock:
 	af_alg_data_wakeup(sk);
+	ctx->write = false;
 	release_sock(sk);
 
 	return copied ?: err;
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index bb5f206447869d344b753b17ce6e5b4aab05ed05..2e43d7704d1d2f6bf34411e63f5d95c41839723b 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -140,6 +140,7 @@ struct af_alg_async_req {
  *			SG?
  * @enc:		Cryptographic operation to be performed when
  *			recvmsg is invoked.
+ * @write:		True if we are in the middle of a write.
  * @init:		True if metadata has been sent.
  * @len:		Length of memory allocated for this data structure.
  * @inflight:		Non-zero when AIO requests are in flight.
@@ -155,10 +156,11 @@ struct af_alg_ctx {
 	size_t used;
 	atomic_t rcvused;
 
-	bool more;
-	bool merge;
-	bool enc;
-	bool init;
+	bool		more:1,
+			merge:1,
+			enc:1,
+			write:1,
+			init:1;
 
 	unsigned int len;