Without that it's not safe to use them in a linked combination with others.

Now combinations like IORING_OP_SENDMSG followed by IORING_OP_SPLICE should be possible.

We already handle short reads and writes for the following opcodes:

- IORING_OP_READV - IORING_OP_READ_FIXED - IORING_OP_READ - IORING_OP_WRITEV - IORING_OP_WRITE_FIXED - IORING_OP_WRITE - IORING_OP_SPLICE - IORING_OP_TEE

Now we have it for these as well:

- IORING_OP_SENDMSG - IORING_OP_SEND - IORING_OP_RECVMSG - IORING_OP_RECV

For IORING_OP_RECVMSG we also check for the MSG_TRUNC and MSG_CTRUNC flags in order to call req_set_fail_links().

cc: stable@vger.kernel.org Signed-off-by: Stefan Metzmacher metze@samba.org --- fs/io_uring.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index e88d9f95d0aa..f8a6a629e4db 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4354,6 +4354,7 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags) struct io_async_msghdr iomsg, *kmsg; struct socket *sock; unsigned flags; + int expected_ret; int ret;

sock = sock_from_file(req->file); @@ -4374,6 +4375,9 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags) else if (issue_flags & IO_URING_F_NONBLOCK) flags |= MSG_DONTWAIT;

+ expected_ret = iov_iter_count(&kmsg->msg.msg_iter); + if (unlikely(expected_ret == MAX_RW_COUNT)) + expected_ret += 1; ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags); if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN) return io_setup_async_msg(req, kmsg); @@ -4384,7 +4388,7 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags) if (kmsg->free_iov) kfree(kmsg->free_iov); req->flags &= ~REQ_F_NEED_CLEANUP; - if (ret < 0) + if (ret != expected_ret) req_set_fail_links(req); __io_req_complete(req, issue_flags, ret, 0); return 0; @@ -4425,7 +4429,7 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags) if (ret == -ERESTARTSYS) ret = -EINTR;

- if (ret < 0) + if (ret != sr->len) req_set_fail_links(req); __io_req_complete(req, issue_flags, ret, 0); return 0; @@ -4577,6 +4581,7 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) struct socket *sock; struct io_buffer *kbuf; unsigned flags; + int expected_ret; int ret, cflags = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

@@ -4608,6 +4613,9 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) else if (force_nonblock) flags |= MSG_DONTWAIT;

+ expected_ret = iov_iter_count(&kmsg->msg.msg_iter); + if (unlikely(expected_ret == MAX_RW_COUNT)) + expected_ret += 1; ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg, kmsg->uaddr, flags); if (force_nonblock && ret == -EAGAIN) @@ -4621,7 +4629,7 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) if (kmsg->free_iov) kfree(kmsg->free_iov); req->flags &= ~REQ_F_NEED_CLEANUP; - if (ret < 0) + if (ret != expected_ret || (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) req_set_fail_links(req); __io_req_complete(req, issue_flags, ret, cflags); return 0; @@ -4675,7 +4683,7 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags) out_free: if (req->flags & REQ_F_BUFFER_SELECTED) cflags = io_put_recv_kbuf(req); - if (ret < 0) + if (ret != sr->len) req_set_fail_links(req); __io_req_complete(req, issue_flags, ret, cflags); return 0;