Re: [PATCH] drm/mipi-dsi: fix UAF on device_add() failure

Linkai Gong <[email protected]> Thu, 6 Aug 2026 17:05:57 +0800
Newsgroups dev.linux.lists.sashiko-reviews
Message-ID <[email protected]>
On Thu, Aug 06, 2026 at 08:09:45 +0000, [email protected] wrote:
> [High] The patch introduces inconsistent ownership semantics for the
> info->node reference on error paths...

Thanks for the review.

The put_device() change is still required: mipi_dsi_device_alloc()
calls device_initialize(), so the error path must release the device
through put_device() rather than kfree().

Regarding of_node: device_set_node(of_fwnode_handle(info->node)) does
not take a reference, while mipi_dsi_dev_release() calls of_node_put().
That imbalance already exists on the success path when the device is
later unregistered; this patch only makes the same release helper run
on the device_add() failure path as well.

I can follow up with a separate change for the of_node refcounting if
the maintainers want that cleaned up. Happy to adjust based on human
reviewer feedback.

Thanks,
Linkai