From 3232dd02af65f2d01be641120d2a710176b0c7a7 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Wed, 3 Jun 2020 18:03:22 +0300 Subject: io_uring: fix {SQ,IO}POLL with unsupported opcodes IORING_SETUP_IOPOLL is defined only for read/write, other opcodes should be disallowed, otherwise it'll get an error as below. Also refuse open/close with SQPOLL, as the polling thread wouldn't know which file table to use. RIP: 0010:io_iopoll_getevents+0x111/0x5a0 Call Trace: ? _raw_spin_unlock_irqrestore+0x24/0x40 ? do_send_sig_info+0x64/0x90 io_iopoll_reap_events.part.0+0x5e/0xa0 io_ring_ctx_wait_and_kill+0x132/0x1c0 io_uring_release+0x20/0x30 __fput+0xcd/0x230 ____fput+0xe/0x10 task_work_run+0x67/0xa0 do_exit+0x353/0xb10 ? handle_mm_fault+0xd4/0x200 ? syscall_trace_enter+0x18c/0x2c0 do_group_exit+0x43/0xa0 __x64_sys_exit_group+0x18/0x20 do_syscall_64+0x60/0x1e0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Pavel Begunkov [axboe: allow provide/remove buffers and files update] Signed-off-by: Jens Axboe --- fs/io_uring.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'fs') diff --git a/fs/io_uring.c b/fs/io_uring.c index 417b7105c6dc..c627dd9ce096 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2766,6 +2766,8 @@ static int __io_splice_prep(struct io_kiocb *req, if (req->flags & REQ_F_NEED_CLEANUP) return 0; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; sp->file_in = NULL; sp->len = READ_ONCE(sqe->len); @@ -2966,6 +2968,8 @@ static int io_fallocate_prep(struct io_kiocb *req, { if (sqe->ioprio || sqe->buf_index || sqe->rw_flags) return -EINVAL; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; req->sync.off = READ_ONCE(sqe->off); req->sync.len = READ_ONCE(sqe->addr); @@ -2991,6 +2995,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) const char __user *fname; int ret; + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; if (sqe->ioprio || sqe->buf_index) return -EINVAL; if (req->flags & REQ_F_FIXED_FILE) @@ -3024,6 +3030,8 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) size_t len; int ret; + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; if (sqe->ioprio || sqe->buf_index) return -EINVAL; if (req->flags & REQ_F_FIXED_FILE) @@ -3263,6 +3271,8 @@ static int io_epoll_ctl_prep(struct io_kiocb *req, #if defined(CONFIG_EPOLL) if (sqe->ioprio || sqe->buf_index) return -EINVAL; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; req->epoll.epfd = READ_ONCE(sqe->fd); req->epoll.op = READ_ONCE(sqe->len); @@ -3307,6 +3317,8 @@ static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) if (sqe->ioprio || sqe->buf_index || sqe->off) return -EINVAL; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; req->madvise.addr = READ_ONCE(sqe->addr); req->madvise.len = READ_ONCE(sqe->len); @@ -3341,6 +3353,8 @@ static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { if (sqe->ioprio || sqe->buf_index || sqe->addr) return -EINVAL; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; req->fadvise.offset = READ_ONCE(sqe->off); req->fadvise.len = READ_ONCE(sqe->len); @@ -3374,6 +3388,8 @@ static int io_fadvise(struct io_kiocb *req, bool force_nonblock) static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; if (sqe->ioprio || sqe->buf_index) return -EINVAL; if (req->flags & REQ_F_FIXED_FILE) @@ -3418,6 +3434,8 @@ static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) */ req->work.flags |= IO_WQ_WORK_NO_CANCEL; + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; if (sqe->ioprio || sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index) return -EINVAL; -- cgit v1.2.3