[PATCH AUTOSEL 5.7 07/60] io_uring: fix req->work corruption
From: Sasha Levin <sashal@kernel.org>
Date: 2020-08-10 19:29:55
Also in:
io-uring, linux-fsdevel, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
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 4e09af1d5d223..80a612d1e12bb 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
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2.25.1