From 100d6b17c06ee4c2b42fdddf0fe4ab77c86eb77e Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Thu, 17 Nov 2022 18:40:17 +0000 Subject: [PATCH] io_uring: fix multishot recv request leaks Having REQ_F_POLLED set doesn't guarantee that the request is executed as a multishot from the polling path. Fortunately for us, if the code thinks it's multishot issue when it's not, it can only ask to skip completion so leaking the request. Use issue_flags to mark multipoll issues. Cc: stable@vger.kernel.org Fixes: 1300ebb20286b ("io_uring: multishot recv") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/37762040ba9c52b81b92a2f5ebfd4ee484088951.1668710222.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/net.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/io_uring/net.c b/io_uring/net.c index a390d3ea486c..ab83da7e80f0 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -67,8 +67,6 @@ struct io_sr_msg { struct io_kiocb *notif; }; -#define IO_APOLL_MULTI_POLLED (REQ_F_APOLL_MULTISHOT | REQ_F_POLLED) - int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown); @@ -591,7 +589,8 @@ static inline void io_recv_prep_retry(struct io_kiocb *req) * again (for multishot). */ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, - unsigned int cflags, bool mshot_finished) + unsigned int cflags, bool mshot_finished, + unsigned issue_flags) { if (!(req->flags & REQ_F_APOLL_MULTISHOT)) { io_req_set_res(req, *ret, cflags); @@ -614,7 +613,7 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, io_req_set_res(req, *ret, cflags); - if (req->flags & REQ_F_POLLED) + if (issue_flags & IO_URING_F_MULTISHOT) *ret = IOU_STOP_MULTISHOT; else *ret = IOU_OK; @@ -773,8 +772,7 @@ retry_multishot: if (ret < min_ret) { 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) { + if (ret == -EAGAIN && (issue_flags & IO_URING_F_MULTISHOT)) { io_kbuf_recycle(req, issue_flags); return IOU_ISSUE_SKIP_COMPLETE; } @@ -803,7 +801,7 @@ retry_multishot: if (kmsg->msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - if (!io_recv_finish(req, &ret, cflags, mshot_finished)) + if (!io_recv_finish(req, &ret, cflags, mshot_finished, issue_flags)) goto retry_multishot; if (mshot_finished) { @@ -869,7 +867,7 @@ retry_multishot: ret = sock_recvmsg(sock, &msg, flags); if (ret < min_ret) { if (ret == -EAGAIN && force_nonblock) { - if ((req->flags & IO_APOLL_MULTI_POLLED) == IO_APOLL_MULTI_POLLED) { + if (issue_flags & IO_URING_F_MULTISHOT) { io_kbuf_recycle(req, issue_flags); return IOU_ISSUE_SKIP_COMPLETE; } @@ -902,7 +900,7 @@ out_free: if (msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - if (!io_recv_finish(req, &ret, cflags, ret <= 0)) + if (!io_recv_finish(req, &ret, cflags, ret <= 0, issue_flags)) goto retry_multishot; return ret; -- 2.34.1