diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2020-12-06 22:22:43 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-12-09 12:04:01 -0700 |
| commit | 31bff9a51b264df6d144931a6a5f1d6cc815ed4b (patch) | |
| tree | ea24ea7493c5b4b97bea3e8b5730743a785cf4de | |
| parent | dad1b1242fd5717af18ae4ac9d12b9f65849e13a (diff) | |
io_uring: fix racy IOPOLL completions
IOPOLL allows buffer remove/provide requests, but they doesn't
synchronise by rules of IOPOLL, namely it have to hold uring_lock.
Cc: <stable@vger.kernel.org> # 5.7+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | fs/io_uring.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 89fd893a6952..d030a4404b8f 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4152,11 +4152,17 @@ static int io_remove_buffers(struct io_kiocb *req, bool force_nonblock, head = idr_find(&ctx->io_buffer_idr, p->bgid); if (head) ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs); - - io_ring_submit_lock(ctx, !force_nonblock); if (ret < 0) req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + + /* need to hold the lock to complete IOPOLL requests */ + if (ctx->flags & IORING_SETUP_IOPOLL) { + __io_req_complete(req, ret, 0, cs); + io_ring_submit_unlock(ctx, !force_nonblock); + } else { + io_ring_submit_unlock(ctx, !force_nonblock); + __io_req_complete(req, ret, 0, cs); + } return 0; } @@ -4241,10 +4247,17 @@ static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock, } } out: - io_ring_submit_unlock(ctx, !force_nonblock); if (ret < 0) req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + + /* need to hold the lock to complete IOPOLL requests */ + if (ctx->flags & IORING_SETUP_IOPOLL) { + __io_req_complete(req, ret, 0, cs); + io_ring_submit_unlock(ctx, !force_nonblock); + } else { + io_ring_submit_unlock(ctx, !force_nonblock); + __io_req_complete(req, ret, 0, cs); + } return 0; } |