io_uring: ensure async punted sendmsg/recvmsg requests copy data
Just like commit f67676d160c6 for read/write requests, this one ensures
that the msghdr data is fully copied if we need to punt a recvmsg or
sendmsg system call to async context.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 1689aea..2700382 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -308,6 +308,13 @@ struct io_timeout {
struct io_timeout_data *data;
};
+struct io_async_msghdr {
+ struct iovec fast_iov[UIO_FASTIOV];
+ struct iovec *iov;
+ struct sockaddr __user *uaddr;
+ struct msghdr msg;
+};
+
struct io_async_rw {
struct iovec fast_iov[UIO_FASTIOV];
struct iovec *iov;
@@ -319,6 +326,7 @@ struct io_async_ctx {
struct io_uring_sqe sqe;
union {
struct io_async_rw rw;
+ struct io_async_msghdr msg;
};
};
@@ -1991,12 +1999,104 @@ static int io_sync_file_range(struct io_kiocb *req,
return 0;
}
-#if defined(CONFIG_NET)
-static int io_send_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- struct io_kiocb **nxt, bool force_nonblock,
- long (*fn)(struct socket *, struct user_msghdr __user *,
- unsigned int))
+static int io_sendmsg_prep(struct io_kiocb *req, struct io_async_ctx *io)
{
+#if defined(CONFIG_NET)
+ const struct io_uring_sqe *sqe = req->sqe;
+ struct user_msghdr __user *msg;
+ unsigned flags;
+
+ flags = READ_ONCE(sqe->msg_flags);
+ msg = (struct user_msghdr __user *)(unsigned long) READ_ONCE(sqe->addr);
+ return sendmsg_copy_msghdr(&io->msg.msg, msg, flags, &io->msg.iov);
+#else
+ return 0;
+#endif
+}
+
+static int io_sendmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+ struct io_kiocb **nxt, bool force_nonblock)
+{
+#if defined(CONFIG_NET)
+ struct socket *sock;
+ int ret;
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+
+ sock = sock_from_file(req->file, &ret);
+ if (sock) {
+ struct io_async_ctx io, *copy;
+ struct sockaddr_storage addr;
+ struct msghdr *kmsg;
+ unsigned flags;
+
+ flags = READ_ONCE(sqe->msg_flags);
+ if (flags & MSG_DONTWAIT)
+ req->flags |= REQ_F_NOWAIT;
+ else if (force_nonblock)
+ flags |= MSG_DONTWAIT;
+
+ if (req->io) {
+ kmsg = &req->io->msg.msg;
+ kmsg->msg_name = &addr;
+ } else {
+ kmsg = &io.msg.msg;
+ kmsg->msg_name = &addr;
+ io.msg.iov = io.msg.fast_iov;
+ ret = io_sendmsg_prep(req, &io);
+ if (ret)
+ goto out;
+ }
+
+ ret = __sys_sendmsg_sock(sock, kmsg, flags);
+ if (force_nonblock && ret == -EAGAIN) {
+ copy = kmalloc(sizeof(*copy), GFP_KERNEL);
+ if (!copy) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ memcpy(©->msg, &io.msg, sizeof(copy->msg));
+ req->io = copy;
+ memcpy(&req->io->sqe, req->sqe, sizeof(*req->sqe));
+ req->sqe = &req->io->sqe;
+ return ret;
+ }
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+ }
+
+out:
+ io_cqring_add_event(req, ret);
+ if (ret < 0 && (req->flags & REQ_F_LINK))
+ req->flags |= REQ_F_FAIL_LINK;
+ io_put_req_find_next(req, nxt);
+ return 0;
+#else
+ return -EOPNOTSUPP;
+#endif
+}
+
+static int io_recvmsg_prep(struct io_kiocb *req, struct io_async_ctx *io)
+{
+#if defined(CONFIG_NET)
+ const struct io_uring_sqe *sqe = req->sqe;
+ struct user_msghdr __user *msg;
+ unsigned flags;
+
+ flags = READ_ONCE(sqe->msg_flags);
+ msg = (struct user_msghdr __user *)(unsigned long) READ_ONCE(sqe->addr);
+ return recvmsg_copy_msghdr(&io->msg.msg, msg, flags, &io->msg.uaddr,
+ &io->msg.iov);
+#else
+ return 0;
+#endif
+}
+
+static int io_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+ struct io_kiocb **nxt, bool force_nonblock)
+{
+#if defined(CONFIG_NET)
struct socket *sock;
int ret;
@@ -2006,6 +2106,9 @@ static int io_send_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
sock = sock_from_file(req->file, &ret);
if (sock) {
struct user_msghdr __user *msg;
+ struct io_async_ctx io, *copy;
+ struct sockaddr_storage addr;
+ struct msghdr *kmsg;
unsigned flags;
flags = READ_ONCE(sqe->msg_flags);
@@ -2016,39 +2119,41 @@ static int io_send_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
msg = (struct user_msghdr __user *) (unsigned long)
READ_ONCE(sqe->addr);
+ if (req->io) {
+ kmsg = &req->io->msg.msg;
+ kmsg->msg_name = &addr;
+ } else {
+ kmsg = &io.msg.msg;
+ kmsg->msg_name = &addr;
+ io.msg.iov = io.msg.fast_iov;
+ ret = io_recvmsg_prep(req, &io);
+ if (ret)
+ goto out;
+ }
- ret = fn(sock, msg, flags);
- if (force_nonblock && ret == -EAGAIN)
+ ret = __sys_recvmsg_sock(sock, kmsg, msg, io.msg.uaddr, flags);
+ if (force_nonblock && ret == -EAGAIN) {
+ copy = kmalloc(sizeof(*copy), GFP_KERNEL);
+ if (!copy) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ memcpy(copy, &io, sizeof(*copy));
+ req->io = copy;
+ memcpy(&req->io->sqe, req->sqe, sizeof(*req->sqe));
+ req->sqe = &req->io->sqe;
return ret;
+ }
if (ret == -ERESTARTSYS)
ret = -EINTR;
}
+out:
io_cqring_add_event(req, ret);
if (ret < 0 && (req->flags & REQ_F_LINK))
req->flags |= REQ_F_FAIL_LINK;
io_put_req_find_next(req, nxt);
return 0;
-}
-#endif
-
-static int io_sendmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- struct io_kiocb **nxt, bool force_nonblock)
-{
-#if defined(CONFIG_NET)
- return io_send_recvmsg(req, sqe, nxt, force_nonblock,
- __sys_sendmsg_sock);
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- struct io_kiocb **nxt, bool force_nonblock)
-{
-#if defined(CONFIG_NET)
- return io_send_recvmsg(req, sqe, nxt, force_nonblock,
- __sys_recvmsg_sock);
#else
return -EOPNOTSUPP;
#endif
@@ -2721,6 +2826,12 @@ static int io_req_defer_prep(struct io_kiocb *req, struct io_async_ctx *io)
case IORING_OP_WRITE_FIXED:
ret = io_write_prep(req, &iovec, &iter, true);
break;
+ case IORING_OP_SENDMSG:
+ ret = io_sendmsg_prep(req, io);
+ break;
+ case IORING_OP_RECVMSG:
+ ret = io_recvmsg_prep(req, io);
+ break;
default:
req->io = io;
return 0;