Hi Zhen, On Wed, Mar 2, 2022 at 11:38 PM Zhen Ni <nizhen@xxxxxxxxxxxxx> wrote: > It will cause null-ptr-deref if platform_get_resource() returns NULL, > we need check the return value. > > Signed-off-by: Zhen Ni <nizhen@xxxxxxxxxxxxx> Thanks for your patch, which is now commit 134a3408c2d3f7e2 ("USB: host: isp116x: check return value after calling platform_get_resource()") upstream. > --- a/drivers/usb/host/isp116x-hcd.c > +++ b/drivers/usb/host/isp116x-hcd.c > @@ -1541,10 +1541,12 @@ static int isp116x_remove(struct platform_device *pdev) > > iounmap(isp116x->data_reg); > res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > - release_mem_region(res->start, 2); > + if (res) > + release_mem_region(res->start, 2); > iounmap(isp116x->addr_reg); > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > - release_mem_region(res->start, 2); > + if (res) > + release_mem_region(res->start, 2); > > usb_put_hcd(hcd); > return 0; Please note that platform_get_resource() cannot return NULL here, as this is the .remove() callback. If we get here, .probe() has already verified the pointers. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds