On Wed, Nov 6, 2019 at 10:41 AM Pan Bian <bianpan2016@xxxxxxx> wrote: > > The next field of the DMA descriptor is written after releasing the > descriptor, which may result in a use-after-free issue. Set the value of > the field before it is released to fix the bug. > Had you chance to read the discussion [1]? I Cc to Gustavo to hear from him about destiny of the change. [1]: http://lkml.iu.edu/hypermail/linux/kernel/1702.1/00843.html > Signed-off-by: Pan Bian <bianpan2016@xxxxxxx> > --- > drivers/usb/gadget/udc/pch_udc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/gadget/udc/pch_udc.c b/drivers/usb/gadget/udc/pch_udc.c > index 265dab2bbfac..c5b8ec908aab 100644 > --- a/drivers/usb/gadget/udc/pch_udc.c > +++ b/drivers/usb/gadget/udc/pch_udc.c > @@ -1518,8 +1518,8 @@ static void pch_udc_free_dma_chain(struct pch_udc_dev *dev, > /* do not free first desc., will be done by free for request */ > td = phys_to_virt(addr); > addr2 = (dma_addr_t)td->next; > - dma_pool_free(dev->data_requests, td, addr); > td->next = 0x00; > + dma_pool_free(dev->data_requests, td, addr); > addr = addr2; > } > req->chain_len = 1; > -- > 2.7.4 > -- With Best Regards, Andy Shevchenko
