| From bc4e1819267f5a9d06729b3335d779673515ffbe Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Sat, 27 Jun 2020 14:04:59 +0300 |
| Subject: io_uring: fix req->work corruption |
| |
| From: Pavel Begunkov <asml.silence@gmail.com> |
| |
| [ Upstream commit 8ef77766ba8694968ed4ba24311b4bacee14f235 ] |
| |
| req->work and req->task_work are in a union, so io_req_task_queue() screws |
| everything that was in work. De-union them for now. |
| |
| [ 704.367253] BUG: unable to handle page fault for address: |
| ffffffffaf7330d0 |
| [ 704.367256] #PF: supervisor write access in kernel mode |
| [ 704.367256] #PF: error_code(0x0003) - permissions violation |
| [ 704.367261] CPU: 6 PID: 1654 Comm: io_wqe_worker-0 Tainted: G |
| I 5.8.0-rc2-00038-ge28d0bdc4863-dirty #498 |
| [ 704.367265] RIP: 0010:_raw_spin_lock+0x1e/0x36 |
| ... |
| [ 704.367276] __alloc_fd+0x35/0x150 |
| [ 704.367279] __get_unused_fd_flags+0x25/0x30 |
| [ 704.367280] io_openat2+0xcb/0x1b0 |
| [ 704.367283] io_issue_sqe+0x36a/0x1320 |
| [ 704.367294] io_wq_submit_work+0x58/0x160 |
| [ 704.367295] io_worker_handle_work+0x2a3/0x430 |
| [ 704.367296] io_wqe_worker+0x2a0/0x350 |
| [ 704.367301] kthread+0x136/0x180 |
| [ 704.367304] ret_from_fork+0x22/0x30 |
| |
| Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> |
| Signed-off-by: Jens Axboe <axboe@kernel.dk> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| fs/io_uring.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| diff --git a/fs/io_uring.c b/fs/io_uring.c |
| index 04694f6c30a04..159338b5f8263 100644 |
| --- a/fs/io_uring.c |
| +++ b/fs/io_uring.c |
| @@ -645,12 +645,12 @@ struct io_kiocb { |
| * restore the work, if needed. |
| */ |
| struct { |
| - struct callback_head task_work; |
| struct hlist_node hash_node; |
| struct async_poll *apoll; |
| }; |
| struct io_wq_work work; |
| }; |
| + struct callback_head task_work; |
| }; |
| |
| #define IO_PLUG_THRESHOLD 2 |
| -- |
| 2.25.1 |
| |
