diff --git a/io_uring/net.c b/io_uring/net.c index 647156c9331a..050ed274170a 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -853,7 +853,7 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) static inline bool io_recv_finish(struct io_kiocb *req, struct io_async_msghdr *kmsg, struct io_br_sel *sel, bool mshot_finished, - unsigned issue_flags) + unsigned issue_flags, int consumed) { struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg); unsigned int cflags = 0; @@ -877,7 +877,7 @@ static inline bool io_recv_finish(struct io_kiocb *req, if (sr->flags & IORING_RECVSEND_BUNDLE) { size_t this_ret = sel->val - sr->done_io; - cflags |= io_put_kbufs(req, this_ret, sel->buf_list, io_bundle_nbufs(kmsg, this_ret)); + cflags |= io_put_kbufs(req, consumed, sel->buf_list, io_bundle_nbufs(kmsg, consumed)); if (sr->flags & IORING_RECV_RETRY) cflags = req->cqe.flags | (cflags & CQE_F_MASK); if (sr->mshot_len && sel->val >= sr->mshot_len) @@ -899,7 +899,7 @@ static inline bool io_recv_finish(struct io_kiocb *req, return false; } } else { - cflags |= io_put_kbuf(req, sel->val, sel->buf_list); + cflags |= io_put_kbuf(req, consumed, sel->buf_list); } /* @@ -1027,6 +1027,8 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) int ret, min_ret = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; bool mshot_finished = true; + int consumed = 0; + size_t len; sock = sock_from_file(req->file); if (unlikely(!sock)) @@ -1042,9 +1044,8 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) retry_multishot: sel.buf_list = NULL; + len = sr->len; if (io_do_buffer_select(req)) { - size_t len = sr->len; - sel = io_buffer_select(req, &len, sr->buf_group, issue_flags); if (!sel.addr) return -ENOBUFS; @@ -1065,6 +1066,7 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) if (req->flags & REQ_F_APOLL_MULTISHOT) { ret = io_recvmsg_multishot(sock, sr, kmsg, flags, &mshot_finished); + consumed = ret; } else { /* disable partial retry for recvmsg with cmsg attached */ if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen) @@ -1072,6 +1074,15 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags); + /* + * With MSG_TRUNC, the net layer will return the full size of + * the packet, even if we only filled part of it in the buffers. + * Adjust the returned size to consume only the real part of the + * buffer. + */ + consumed = ret; + if (ret > 0) + consumed = min_t(size_t, ret, len); } if (ret < min_ret) { @@ -1098,7 +1109,7 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) io_kbuf_recycle(req, sel.buf_list, issue_flags); sel.val = ret; - if (!io_recv_finish(req, kmsg, &sel, mshot_finished, issue_flags)) + if (!io_recv_finish(req, kmsg, &sel, mshot_finished, issue_flags, consumed)) goto retry_multishot; return sel.val; @@ -1185,9 +1196,10 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) struct io_br_sel sel; struct socket *sock; unsigned flags; - int ret, min_ret = 0; + int ret, min_ret = 0, consumed = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; bool mshot_finished; + size_t len = 0; sock = sock_from_file(req->file); if (unlikely(!sock)) @@ -1215,6 +1227,7 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) retry_multishot: sel.buf_list = NULL; + len = sr->len; if (io_do_buffer_select(req)) { sel.val = sr->len; ret = io_recv_buf_select(req, kmsg, &sel, issue_flags); @@ -1222,6 +1235,7 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) kmsg->msg.msg_inq = -1; goto out_free; } + len = ret; sr->buf = NULL; } @@ -1252,6 +1266,17 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) } mshot_finished = ret <= 0; + + /* + * With MSG_TRUNC, the net layer will return the full size of + * the packet, even if we only filled part of it in the buffers. + * Adjust the returned size to consume only the real part of the + * buffer. + */ + consumed = ret; + if (ret > 0) + consumed = min_t(size_t, ret, len); + if (ret > 0) ret += sr->done_io; else if (sr->done_io) @@ -1260,7 +1285,7 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) io_kbuf_recycle(req, sel.buf_list, issue_flags); sel.val = ret; - if (!io_recv_finish(req, kmsg, &sel, mshot_finished, issue_flags)) + if (!io_recv_finish(req, kmsg, &sel, mshot_finished, issue_flags, consumed)) goto retry_multishot; return sel.val;