io_uring-5.5-20191220
io_uring: io_wq_submit_work() should not touch req->rw
I've been chasing a weird and obscure crash that was userspace stack
corruption, and finally narrowed it down to a bit flip that made a
stack address invalid. io_wq_submit_work() unconditionally flips
the req->rw.ki_flags IOCB_NOWAIT bit, but since it's a generic work
handler, this isn't valid. Normal read/write operations own that
part of the request, on other types it could be something else.
Move the IOCB_NOWAIT clear to the read/write handlers where it belongs.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 file changed
