In the Linux kernel, the following vulnerability has been resolved: usb: gadget: goku_udc: avoid NULL deref of dev->driver in INT_USBRESET log goku_irq() handles a number of bus events under a single ep0 path. It already guards the gadget driver suspend/resume callbacks against a NULL ->driver: if (dev->gadget.speed != USB_SPEED_UNKNOWN && dev->driver && dev->driver->resume) { spin_unlock(&dev->lock); dev->driver->resume(&dev->gadget); ... } but the very next branch unconditionally dereferences dev->driver when an INT_USBRESET arrives: if (stat & INT_USBRESET) { ACK(INT_USBRESET); INFO(dev, "USB reset done, gadget %s\n", dev->driver->driver.name); } If the controller raises INT_USBRESET before any gadget driver has been bound (or after one has been unbound), dev->driver is NULL and the printk dereferences NULL. smatch flags the inconsistency: drivers/usb/gadget/udc/goku_udc.c:1618 goku_irq() error: we previously assumed 'dev->driver' could be null (see line 1607) Fall back to a placeholder when the gadget driver is not bound. No functional change while a gadget driver is bound.
https://git.kernel.org/stable/c/ea2901a4a90afc662e4d023542d91f10ab10fd3c
https://git.kernel.org/stable/c/d7b33afbf9b54b61cb423af9663df54eae11d3b1
https://git.kernel.org/stable/c/a018d4195114ca2cf79858cc45c98581dee4795b
https://git.kernel.org/stable/c/999ff3bf665f2abfb6af519ef3d6d42b061d3c15
https://git.kernel.org/stable/c/5bf5e3fba9bc7dfd69701521dbe9809f8ccbdb02
https://git.kernel.org/stable/c/28d78783a871cdb7a637dcb72452ff7d303430ae
https://git.kernel.org/stable/c/10d7fc3008d5b7ec03af8e08927f1d090014c2af