Overview
About vulnerability
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.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.4.0 (+19 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Planned | — |
| Debian 13 | Will Not Fix |
17 kernels
|