Re: [PATCH v2] iio: buffer: hw-consumer: fix use-after-free in error path

Joshua Crofts
2026-05-01T14:20:01Z

On Thu, 30 Apr 2026 at 15:29, Felix Gu <ustc.gu@gmail.com> wrote:
>
> In the err_put_buffers cleanup path of iio_hw_consumer_alloc(), the code
> was using list_for_each_entry() to iterate through buffers while calling
> iio_buffer_put() which can free the current buffer if refcount drops to 0.
> The list_for_each_entry() loop macro then evaluates buf->head.next to
> continue iteration, accessing the freed buffer.
>
> Fix this by using list_for_each_entry_safe().
>
> Fixes: 48b66f8f936f ("iio: Add hardware consumer buffer support")
> Reported-by: sashiko <sashiko-bot@kernel.org>
> Closes: https://sashiko.dev/#/patchset/20260427-iio_buf-v1-1-2bbdac844647%40gmail.com

FYI, Sashiko reported 2 additional regressions (neither introduced by
your patches), one of them critical. Maybe another patch would be good?

https://sashiko.dev/#/patchset/20260430-iio-buf-v2-1-84c2231dea5e%40gmail.com?part=1

--
Kind regards

CJD