Re: [PATCH v2] usb: gadget: aspeed_udc: check endpoint DMA allocation
Andrew Jeffery <[email protected]> Thu, 11 Jun 2026 14:36:53 +0930
| Newsgroups | org.ozlabs.lists.linux-aspeed,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel,org.kernel.vger.linux-usb |
|---|---|
| Message-ID | <a4f09170d3d618d285f7019c82e63142b268d6ce.camel@codeconstruct.com.au> |
On Wed, 2026-06-10 at 20:10 +0800, Ruoyu Wang wrote:
> ast_udc_probe() allocates a coherent DMA buffer used as the backing store
> for endpoint buffers. ast_udc_init_ep() derives per-endpoint buffer
> pointers from udc->ep0_buf, so a failed allocation is dereferenced during
> probe.
>
> Check the allocation before endpoint setup. The existing probe error path
> called ast_udc_remove(), which unregisters the gadget unconditionally and
> is not safe before usb_add_gadget_udc() succeeds. Add a local cleanup
> helper for probe failures so pre-registration failures only unwind the
> resources that were actually initialized.
>
> This was found by a local static analysis checker for unchecked allocator
> returns while scanning Linux 6.16. The change was checked by applying it
> to current mainline and by running checkpatch. I do not have access to
> Aspeed UDC hardware, so no runtime testing was performed.
>
> Fixes: 055276c13205 ("usb: gadget: add Aspeed ast2600 udc driver")
> Signed-off-by: Ruoyu Wang <[email protected]>
Reviewed-by: Andrew Jeffery <[email protected]>