diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 499679134961..4c9b11e2e991 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -613,4 +613,11 @@ struct io_uring_file_index_range { __u64 resv; }; +struct io_uring_recvmsg_out { + __u32 namelen; + __u32 controllen; + __u32 payloadlen; + __u32 flags; +}; + #endif diff --git a/io_uring/net.c b/io_uring/net.c index 5bc3440a8290..616d5f04cc74 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -325,6 +325,21 @@ int io_send(struct io_kiocb *req, unsigned int issue_flags) return IOU_OK; } +static bool io_recvmsg_multishot_overflow(struct io_async_msghdr *iomsg) +{ + unsigned long hdr; + + if (check_add_overflow(sizeof(struct io_uring_recvmsg_out), + (unsigned long)iomsg->namelen, &hdr)) + return true; + if (check_add_overflow(hdr, iomsg->controllen, &hdr)) + return true; + if (hdr > INT_MAX) + return true; + + return false; +} + static int __io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg) { @@ -352,6 +367,13 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = iomsg->fast_iov[0].iov_len; iomsg->free_iov = NULL; } + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + iomsg->namelen = msg.msg_namelen; + iomsg->controllen = msg.msg_controllen; + if (io_recvmsg_multishot_overflow(iomsg)) + return -EOVERFLOW; + } } else { iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, msg.msg_iov, msg.msg_iovlen, UIO_FASTIOV, @@ -399,6 +421,13 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = clen; iomsg->free_iov = NULL; } + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + iomsg->namelen = msg.msg_namelen; + iomsg->controllen = msg.msg_controllen; + if (io_recvmsg_multishot_overflow(iomsg)) + return -EOVERFLOW; + } } else { iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, (struct iovec __user *)uiov, msg.msg_iovlen, @@ -455,8 +484,6 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sr->msg_flags & MSG_ERRQUEUE) req->flags |= REQ_F_CLEAR_POLLIN; if (sr->flags & IORING_RECV_MULTISHOT) { - if (req->opcode == IORING_OP_RECVMSG) - return -EINVAL; if (!(req->flags & REQ_F_BUFFER_SELECT)) return -EINVAL; if (sr->msg_flags & MSG_WAITALL) @@ -483,12 +510,13 @@ static inline void io_recv_prep_retry(struct io_kiocb *req) } /* - * Finishes io_recv + * Finishes io_recv and io_recvmsg. * * Returns true if it is actually finished, or false if it should run * again (for multishot). */ -static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int cflags) +static inline bool io_recv_finish(struct io_kiocb *req, int *ret, + unsigned int cflags, bool mshot_finished) { if (!(req->flags & REQ_F_APOLL_MULTISHOT)) { io_req_set_res(req, *ret, cflags); @@ -496,7 +524,7 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int c return true; } - if (*ret > 0) { + if (!mshot_finished) { if (io_post_aux_cqe(req->ctx, req->cqe.user_data, *ret, cflags | IORING_CQE_F_MORE, false)) { io_recv_prep_retry(req); @@ -518,6 +546,90 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int c return true; } +static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg, + struct io_sr_msg *sr, void __user **buf, + size_t *len) +{ + unsigned long ubuf = (unsigned long) *buf; + unsigned long hdr; + + hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen + + kmsg->controllen; + if (*len < hdr) + return -EFAULT; + + if (kmsg->controllen) { + unsigned long control = ubuf + hdr - kmsg->controllen; + + kmsg->msg.msg_control_user = (void *) control; + kmsg->msg.msg_controllen = kmsg->controllen; + } + + sr->buf = *buf; /* stash for later copy */ + *buf = (void *) (ubuf + hdr); + kmsg->payloadlen = *len = *len - hdr; + return 0; +} + +struct io_recvmsg_multishot_hdr { + struct io_uring_recvmsg_out msg; + struct sockaddr_storage addr; +}; + +static int io_recvmsg_multishot(struct socket *sock, struct io_sr_msg *io, + struct io_async_msghdr *kmsg, + unsigned int flags, bool *finished) +{ + int err; + int copy_len; + struct io_recvmsg_multishot_hdr hdr; + + if (kmsg->namelen) + kmsg->msg.msg_name = &hdr.addr; + kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT); + kmsg->msg.msg_namelen = 0; + + if (sock->file->f_flags & O_NONBLOCK) + flags |= MSG_DONTWAIT; + + err = sock_recvmsg(sock, &kmsg->msg, flags); + *finished = err <= 0; + if (err < 0) + return err; + + hdr.msg = (struct io_uring_recvmsg_out) { + .controllen = kmsg->controllen - kmsg->msg.msg_controllen, + .flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT + }; + + hdr.msg.payloadlen = err; + if (err > kmsg->payloadlen) + err = kmsg->payloadlen; + + copy_len = sizeof(struct io_uring_recvmsg_out); + if (kmsg->msg.msg_namelen > kmsg->namelen) + copy_len += kmsg->namelen; + else + copy_len += kmsg->msg.msg_namelen; + + /* + * "fromlen shall refer to the value before truncation.." + * 1003.1g + */ + hdr.msg.namelen = kmsg->msg.msg_namelen; + + /* ensure that there is no gap between hdr and sockaddr_storage */ + BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) != + sizeof(struct io_uring_recvmsg_out)); + if (copy_to_user(io->buf, &hdr, copy_len)) { + *finished = true; + return -EFAULT; + } + + return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen + + kmsg->controllen + err; +} + int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) { struct io_sr_msg *sr = io_kiocb_to_cmd(req); @@ -527,6 +639,7 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) unsigned flags; int ret, min_ret = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + bool mshot_finished = true; sock = sock_from_file(req->file); if (unlikely(!sock)) @@ -545,16 +658,27 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return io_setup_async_msg(req, kmsg, issue_flags); +retry_multishot: if (io_do_buffer_select(req)) { void __user *buf; + size_t len = sr->len; - buf = io_buffer_select(req, &sr->len, issue_flags); + buf = io_buffer_select(req, &len, issue_flags); if (!buf) return -ENOBUFS; + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + ret = io_recvmsg_prep_multishot(kmsg, sr, &buf, &len); + if (ret) { + io_kbuf_recycle(req, issue_flags); + return ret; + } + } + kmsg->fast_iov[0].iov_base = buf; - kmsg->fast_iov[0].iov_len = sr->len; + kmsg->fast_iov[0].iov_len = len; iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1, - sr->len); + len); } flags = sr->msg_flags; @@ -564,10 +688,23 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) min_ret = iov_iter_count(&kmsg->msg.msg_iter); kmsg->msg.msg_get_inq = 1; - ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags); + if (req->flags & REQ_F_APOLL_MULTISHOT) + ret = io_recvmsg_multishot(sock, sr, kmsg, flags, + &mshot_finished); + else + ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, + kmsg->uaddr, flags); + if (ret < min_ret) { - if (ret == -EAGAIN && force_nonblock) - return io_setup_async_msg(req, kmsg, issue_flags); + if (ret == -EAGAIN && force_nonblock) { + ret = io_setup_async_msg(req, kmsg, issue_flags); + if (ret == -EAGAIN && (req->flags & IO_APOLL_MULTI_POLLED) == + IO_APOLL_MULTI_POLLED) { + io_kbuf_recycle(req, issue_flags); + return IOU_ISSUE_SKIP_COMPLETE; + } + return ret; + } if (ret == -ERESTARTSYS) ret = -EINTR; if (ret > 0 && io_net_retry(sock, flags)) { @@ -580,11 +717,6 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) req_set_fail(req); } - /* fast path, check for non-NULL to avoid function call */ - if (kmsg->free_iov) - kfree(kmsg->free_iov); - io_netmsg_recycle(req, issue_flags); - req->flags &= ~REQ_F_NEED_CLEANUP; if (ret > 0) ret += sr->done_io; else if (sr->done_io) @@ -596,8 +728,18 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) if (kmsg->msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - io_req_set_res(req, ret, cflags); - return IOU_OK; + if (!io_recv_finish(req, &ret, cflags, mshot_finished)) + goto retry_multishot; + + if (mshot_finished) { + io_netmsg_recycle(req, issue_flags); + /* fast path, check for non-NULL to avoid function call */ + if (kmsg->free_iov) + kfree(kmsg->free_iov); + req->flags &= ~REQ_F_NEED_CLEANUP; + } + + return ret; } int io_recv(struct io_kiocb *req, unsigned int issue_flags) @@ -684,7 +826,7 @@ out_free: if (msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - if (!io_recv_finish(req, &ret, cflags)) + if (!io_recv_finish(req, &ret, cflags, ret <= 0)) goto retry_multishot; return ret; diff --git a/io_uring/net.h b/io_uring/net.h index 178a6d8b76e0..db20ce9d6546 100644 --- a/io_uring/net.h +++ b/io_uring/net.h @@ -9,6 +9,12 @@ struct io_async_msghdr { union { struct iovec fast_iov[UIO_FASTIOV]; + struct { + struct iovec fast_iov_one; + __kernel_size_t controllen; + int namelen; + __kernel_size_t payloadlen; + }; struct io_cache_entry cache; }; /* points to an allocated iov, if NULL we use fast_iov instead */