From: Jens Axboe <axboe@xxxxxxxxx> commit c0a9d496e0fece67db777bd48550376cf2960c47 upstream. Some file systems, ocfs2 in this case, will return -EOPNOTSUPP for an IOCB_NOWAIT read/write attempt. While this can be argued to be correct, the usual return value for something that requires blocking issue is -EAGAIN. A refactoring io_uring commit dropped calling kiocb_done() for negative return values, which is otherwise where we already do that transformation. To ensure we catch it in both spots, check it in __io_read() itself as well. Reported-by: Robert Sander <r.sander@xxxxxxxxxxxxxxxxxxx> Link: https://fosstodon.org/@gurubert@xxxxxxxxxxxxxxxxxxxx/113112431889638440 Cc: stable@xxxxxxxxxxxxxxx Fixes: a08d195b586a ("io_uring/rw: split io_read() into a helper") Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- io_uring/rw.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -855,6 +855,14 @@ static int __io_read(struct io_kiocb *re ret = io_iter_do_read(rw, &io->iter); + /* + * Some file systems like to return -EOPNOTSUPP for an IOCB_NOWAIT + * issue, even though they should be returning -EAGAIN. To be safe, + * retry from blocking context for either. + */ + if (ret == -EOPNOTSUPP && force_nonblock) + ret = -EAGAIN; + if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) { req->flags &= ~REQ_F_REISSUE; /* If we can poll, just do that. */ Patches currently in stable-queue which might be from axboe@xxxxxxxxx are queue-6.11/nbd-correct-the-maximum-value-for-discard-sectors.patch queue-6.11/block-bfq-fix-possible-uaf-for-bfqq-bic-with-merge-c.patch queue-6.11/io_uring-rw-treat-eopnotsupp-for-iocb_nowait-like-eagain.patch queue-6.11/io_uring-io-wq-do-not-allow-pinning-outside-of-cpuse.patch queue-6.11/nbd-fix-race-between-timeout-and-normal-completion.patch queue-6.11/block-bfq-fix-uaf-for-accessing-waker_bfqq-after-spl.patch queue-6.11/block-bfq-choose-the-last-bfqq-from-merge-chain-in-b.patch queue-6.11/ublk-move-zone-report-data-out-of-request-pdu.patch queue-6.11/lib-sbitmap-define-swap_lock-as-raw_spinlock_t.patch queue-6.11/block-bfq-don-t-break-merge-chain-in-bfq_split_bfqq.patch queue-6.11/block-fix-potential-invalid-pointer-dereference-in-b.patch queue-6.11/io_uring-check-for-presence-of-task_work-rather-than-tif_notify_signal.patch queue-6.11/io_uring-sqpoll-do-not-allow-pinning-outside-of-cpuset.patch queue-6.11/block-bfq-fix-procress-reference-leakage-for-bfqq-in.patch queue-6.11/io_uring-io-wq-inherit-cpuset-of-cgroup-in-io-worker.patch
