1 files changed, 57 insertions, 104 deletions

diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c
index cbc85bca006f..754e94a0e07f 100644
--- a/fs/smb/client/smbdirect.c
+++ b/fs/smb/client/smbdirect.c
@@ -907,8 +907,10 @@ wait_send_queue:
 			.local_dma_lkey	= sc->ib.pd->local_dma_lkey,
 			.direction	= DMA_TO_DEVICE,
 		};
+		size_t payload_len = umin(*_remaining_data_length,
+					  sp->max_send_size - sizeof(*packet));
 
-		rc = smb_extract_iter_to_rdma(iter, *_remaining_data_length,
+		rc = smb_extract_iter_to_rdma(iter, payload_len,
 					      &extract);
 		if (rc < 0)
 			goto err_dma;
@@ -1013,6 +1015,27 @@ static int smbd_post_send_empty(struct smbd_connection *info)
 	return smbd_post_send_iter(info, NULL, &remaining_data_length);
 }
 
+static int smbd_post_send_full_iter(struct smbd_connection *info,
+				    struct iov_iter *iter,
+				    int *_remaining_data_length)
+{
+	int rc = 0;
+
+	/*
+	 * smbd_post_send_iter() respects the
+	 * negotiated max_send_size, so we need to
+	 * loop until the full iter is posted
+	 */
+
+	while (iov_iter_count(iter) > 0) {
+		rc = smbd_post_send_iter(info, iter, _remaining_data_length);
+		if (rc < 0)
+			break;
+	}
+
+	return rc;
+}
+
 /*
  * Post a receive request to the transport
  * The remote peer can only send data when a receive request is posted
@@ -1452,6 +1475,9 @@ static int allocate_caches_and_workqueue(struct smbd_connection *info)
 	char name[MAX_NAME_LEN];
 	int rc;
 
+	if (WARN_ON_ONCE(sp->max_recv_size < sizeof(struct smbdirect_data_transfer)))
+		return -ENOMEM;
+
 	scnprintf(name, MAX_NAME_LEN, "smbd_request_%p", info);
 	info->request_cache =
 		kmem_cache_create(
@@ -1469,12 +1495,17 @@ static int allocate_caches_and_workqueue(struct smbd_connection *info)
 		goto out1;
 
 	scnprintf(name, MAX_NAME_LEN, "smbd_response_%p", info);
+
+	struct kmem_cache_args response_args = {
+		.align		= __alignof__(struct smbd_response),
+		.useroffset	= (offsetof(struct smbd_response, packet) +
+				   sizeof(struct smbdirect_data_transfer)),
+		.usersize	= sp->max_recv_size - sizeof(struct smbdirect_data_transfer),
+	};
 	info->response_cache =
-		kmem_cache_create(
-			name,
-			sizeof(struct smbd_response) +
-				sp->max_recv_size,
-			0, SLAB_HWCACHE_ALIGN, NULL);
+		kmem_cache_create(name,
+				  sizeof(struct smbd_response) + sp->max_recv_size,
+				  &response_args, SLAB_HWCACHE_ALIGN);
 	if (!info->response_cache)
 		goto out2;
 
@@ -1747,35 +1778,39 @@ try_again:
 }
 
 /*
- * Receive data from receive reassembly queue
+ * Receive data from the transport's receive reassembly queue
  * All the incoming data packets are placed in reassembly queue
- * buf: the buffer to read data into
+ * iter: the buffer to read data into
  * size: the length of data to read
  * return value: actual data read
- * Note: this implementation copies the data from reassebmly queue to receive
+ *
+ * Note: this implementation copies the data from reassembly queue to receive
  * buffers used by upper layer. This is not the optimal code path. A better way
  * to do it is to not have upper layer allocate its receive buffers but rather
  * borrow the buffer from reassembly queue, and return it after data is
  * consumed. But this will require more changes to upper layer code, and also
  * need to consider packet boundaries while they still being reassembled.
  */
-static int smbd_recv_buf(struct smbd_connection *info, char *buf,
-		unsigned int size)
+int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
 {
 	struct smbdirect_socket *sc = &info->socket;
 	struct smbd_response *response;
 	struct smbdirect_data_transfer *data_transfer;
+	size_t size = iov_iter_count(&msg->msg_iter);
 	int to_copy, to_read, data_read, offset;
 	u32 data_length, remaining_data_length, data_offset;
 	int rc;
 
+	if (WARN_ON_ONCE(iov_iter_rw(&msg->msg_iter) == WRITE))
+		return -EINVAL; /* It's a bug in upper layer to get there */
+
 again:
 	/*
 	 * No need to hold the reassembly queue lock all the time as we are
 	 * the only one reading from the front of the queue. The transport
 	 * may add more entries to the back of the queue at the same time
 	 */
-	log_read(INFO, "size=%d info->reassembly_data_length=%d\n", size,
+	log_read(INFO, "size=%zd info->reassembly_data_length=%d\n", size,
 		info->reassembly_data_length);
 	if (info->reassembly_data_length >= size) {
 		int queue_length;
@@ -1813,7 +1848,10 @@ again:
 			if (response->first_segment && size == 4) {
 				unsigned int rfc1002_len =
 					data_length + remaining_data_length;
-				*((__be32 *)buf) = cpu_to_be32(rfc1002_len);
+				__be32 rfc1002_hdr = cpu_to_be32(rfc1002_len);
+				if (copy_to_iter(&rfc1002_hdr, sizeof(rfc1002_hdr),
+						 &msg->msg_iter) != sizeof(rfc1002_hdr))
+					return -EFAULT;
 				data_read = 4;
 				response->first_segment = false;
 				log_read(INFO, "returning rfc1002 length %d\n",
@@ -1822,10 +1860,9 @@ again:
 			}
 
 			to_copy = min_t(int, data_length - offset, to_read);
-			memcpy(
-				buf + data_read,
-				(char *)data_transfer + data_offset + offset,
-				to_copy);
+			if (copy_to_iter((char *)data_transfer + data_offset + offset,
+					 to_copy, &msg->msg_iter) != to_copy)
+				return -EFAULT;
 
 			/* move on to the next buffer? */
 			if (to_copy == data_length - offset) {
@@ -1891,90 +1928,6 @@ read_rfc1002_done:
 }
 
 /*
- * Receive a page from receive reassembly queue
- * page: the page to read data into
- * to_read: the length of data to read
- * return value: actual data read
- */
-static int smbd_recv_page(struct smbd_connection *info,
-		struct page *page, unsigned int page_offset,
-		unsigned int to_read)
-{
-	struct smbdirect_socket *sc = &info->socket;
-	int ret;
-	char *to_address;
-	void *page_address;
-
-	/* make sure we have the page ready for read */
-	ret = wait_event_interruptible(
-		info->wait_reassembly_queue,
-		info->reassembly_data_length >= to_read ||
-			sc->status != SMBDIRECT_SOCKET_CONNECTED);
-	if (ret)
-		return ret;
-
-	/* now we can read from reassembly queue and not sleep */
-	page_address = kmap_atomic(page);
-	to_address = (char *) page_address + page_offset;
-
-	log_read(INFO, "reading from page=%p address=%p to_read=%d\n",
-		page, to_address, to_read);
-
-	ret = smbd_recv_buf(info, to_address, to_read);
-	kunmap_atomic(page_address);
-
-	return ret;
-}
-
-/*
- * Receive data from transport
- * msg: a msghdr point to the buffer, can be ITER_KVEC or ITER_BVEC
- * return: total bytes read, or 0. SMB Direct will not do partial read.
- */
-int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
-{
-	char *buf;
-	struct page *page;
-	unsigned int to_read, page_offset;
-	int rc;
-
-	if (iov_iter_rw(&msg->msg_iter) == WRITE) {
-		/* It's a bug in upper layer to get there */
-		cifs_dbg(VFS, "Invalid msg iter dir %u\n",
-			 iov_iter_rw(&msg->msg_iter));
-		rc = -EINVAL;
-		goto out;
-	}
-
-	switch (iov_iter_type(&msg->msg_iter)) {
-	case ITER_KVEC:
-		buf = msg->msg_iter.kvec->iov_base;
-		to_read = msg->msg_iter.kvec->iov_len;
-		rc = smbd_recv_buf(info, buf, to_read);
-		break;
-
-	case ITER_BVEC:
-		page = msg->msg_iter.bvec->bv_page;
-		page_offset = msg->msg_iter.bvec->bv_offset;
-		to_read = msg->msg_iter.bvec->bv_len;
-		rc = smbd_recv_page(info, page, page_offset, to_read);
-		break;
-
-	default:
-		/* It's a bug in upper layer to get there */
-		cifs_dbg(VFS, "Invalid msg type %d\n",
-			 iov_iter_type(&msg->msg_iter));
-		rc = -EINVAL;
-	}
-
-out:
-	/* SMBDirect will read it all or nothing */
-	if (rc > 0)
-		msg->msg_iter.count = 0;
-	return rc;
-}
-
-/*
  * Send data to transport
  * Each rqst is transported as a SMBDirect payload
  * rqst: the data to write
@@ -2032,14 +1985,14 @@ int smbd_send(struct TCP_Server_Info *server,
 			klen += rqst->rq_iov[i].iov_len;
 		iov_iter_kvec(&iter, ITER_SOURCE, rqst->rq_iov, rqst->rq_nvec, klen);
 
-		rc = smbd_post_send_iter(info, &iter, &remaining_data_length);
+		rc = smbd_post_send_full_iter(info, &iter, &remaining_data_length);
 		if (rc < 0)
 			break;
 
 		if (iov_iter_count(&rqst->rq_iter) > 0) {
 			/* And then the data pages if there are any */
-			rc = smbd_post_send_iter(info, &rqst->rq_iter,
-						 &remaining_data_length);
+			rc = smbd_post_send_full_iter(info, &rqst->rq_iter,
+						      &remaining_data_length);
 			if (rc < 0)
 				break;
 		}