diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-04-17 10:10:34 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-27 14:41:17 +0200 |
| commit | d64f8bae0685c6938a8a3646b3c7f63ea9ae6408 (patch) | |
| tree | 83f6d9d730d0a315cdf878629d9e7a503ad68ba6 | |
| parent | 3b1ef649c0e66b1e868eb0e88952806ae00a476c (diff) | |
io_uring: fix leaks on IOPOLL and CQE_SKIP
commit c0713540f6d55c53dca65baaead55a5a8b20552d upstream.
If all completed requests in io_do_iopoll() were marked with
REQ_F_CQE_SKIP, we'll not only skip CQE posting but also
io_free_batch_list() leaking memory and resources.
Move @nr_events increment before REQ_F_CQE_SKIP check. We'll potentially
return the value greater than the real one, but iopolling will deal with
it and the userspace will re-iopoll if needed. In anyway, I don't think
there are many use cases for REQ_F_CQE_SKIP + IOPOLL.
Fixes: 83a13a4181b0e ("io_uring: tweak iopoll CQE_SKIP event counting")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5072fc8693fbfd595f89e5d4305bfcfd5d2f0a64.1650186611.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/io_uring.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 9349d7e0754f..fbba8342172a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2612,11 +2612,10 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin) /* order with io_complete_rw_iopoll(), e.g. ->result updates */ if (!smp_load_acquire(&req->iopoll_completed)) break; + nr_events++; if (unlikely(req->flags & REQ_F_CQE_SKIP)) continue; - __io_fill_cqe(ctx, req->user_data, req->result, io_put_kbuf(req)); - nr_events++; } if (unlikely(!nr_events)) |