Commit 36703247 authored Jul 25, 2019 by Jens Axboe

io_uring: ensure ->list is initialized for poll commands



Daniel reports that when testing an http server that uses io_uring
to poll for incoming connections, sometimes it hard crashes. This is
due to an uninitialized list member for the io_uring request. Normally
this doesn't trigger and none of the test cases caught it.

Reported-by: Daniel Kozak <kozzi11@gmail.com>
Tested-by: Daniel Kozak <kozzi11@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 77ce56e2

fs/io_uring.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1666,6 +1666,8 @@ static int io_poll_add(struct io_kiocb req, const struct io_uring_sqe sqe)
		INIT_LIST_HEAD(&poll->wait.entry);
		init_waitqueue_func_entry(&poll->wait, io_poll_wake);

		INIT_LIST_HEAD(&req->list);

		mask = vfs_poll(poll->file, &ipt.pt) & poll->events;

		spin_lock_irq(&ctx->completion_lock);