On 9/3/21 3:55 PM, Al Viro wrote: > On Fri, Sep 03, 2021 at 02:55:26PM -0600, Jens Axboe wrote: >> On 8/23/21 4:18 AM, Pavel Begunkov wrote: >>> iov_iter_revert() doesn't go well with iov_iter_truncate() in all >>> cases, see 2/2 for the bug description. As mentioned there the current >>> problems is because of generic_write_checks(), but there was also a >>> similar case fixed in 5.12, which should have been triggerable by normal >>> write(2)/read(2) and others. >>> >>> It may be better to enforce reexpands as a long term solution, but for >>> now this patchset is quickier and easier to backport. >>> >>> v2: don't fail if it was justly fully reverted >>> v3: use truncated size + reexapand based approach >> >> Al, let's get this upstream. How do you want to handle it? I can take >> it through the io_uring tree, or it can go through your tree. I really >> don't care which route it takes, but we should get this upstream as >> it solves a real problem. > > Grabbed, will test and send a pull request... Thanks Al! We should mark these for stable as well. -- Jens Axboe
