From eb6cd6d3d8abeac5d7e8251b898067184afdad8a Mon Sep 17 00:00:00 2001 From: Gary Guo Date: Tue, 7 Jul 2026 13:26:45 +0100 Subject: [PATCH] usb: xusbatm: don't rely on id table pointer arithmetic The current code is broken when dynamic ID is involved; in such cases usb_device_id parameter of probe lives on the heap and the pointer arithmetic will get an index that is wildly out of bound. xusbatm initialize the USB device IDs dynamically so it can just use driver_info too. Even with conversion, xusbatm still cannot support dynamic IDs, so also set no_dynamic_id. Signed-off-by: Gary Guo Link: https://patch.msgid.link/20260707-usb_dyn_id_uaf-v2-6-632dcf3adfba@garyguo.net Signed-off-by: Greg Kroah-Hartman --- drivers/usb/atm/xusbatm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/usb/atm/xusbatm.c b/drivers/usb/atm/xusbatm.c index 0befbf63d1cc..5c1e1f521555 100644 --- a/drivers/usb/atm/xusbatm.c +++ b/drivers/usb/atm/xusbatm.c @@ -79,7 +79,7 @@ static int xusbatm_bind(struct usbatm_data *usbatm, struct usb_interface *intf, const struct usb_device_id *id) { struct usb_device *usb_dev = interface_to_usbdev(intf); - int drv_ix = id - xusbatm_usb_ids; + int drv_ix = id->driver_info; int rx_alt = rx_altsetting[drv_ix]; int tx_alt = tx_altsetting[drv_ix]; struct usb_interface *rx_intf = xusbatm_find_intf(usb_dev, rx_alt, rx_endpoint[drv_ix]); @@ -168,7 +168,8 @@ static struct usb_driver xusbatm_usb_driver = { .name = xusbatm_driver_name, .probe = xusbatm_usb_probe, .disconnect = usbatm_usb_disconnect, - .id_table = xusbatm_usb_ids + .id_table = xusbatm_usb_ids, + .no_dynamic_id = 1, }; static int __init xusbatm_init(void) @@ -190,6 +191,7 @@ static int __init xusbatm_init(void) xusbatm_usb_ids[i].match_flags = USB_DEVICE_ID_MATCH_DEVICE; xusbatm_usb_ids[i].idVendor = vendor[i]; xusbatm_usb_ids[i].idProduct = product[i]; + xusbatm_usb_ids[i].driver_info = i; xusbatm_drivers[i].driver_name = xusbatm_driver_name; xusbatm_drivers[i].bind = xusbatm_bind;