In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: gadget: Free gadget structure only after freeing endpoints As part of commit e81a7018d93a (usb: dwc3: allocate gadget structure dynamically) the dwc3_gadget_release() was added which will free the dwc->gadget structure upon the device\'s removal when usb_del_gadget_udc() is called in dwc3_gadget_exit(). However, simply freeing the gadget results a dangling pointer situation: the endpoints created in dwc3_gadget_init_endpoints() have their dep->endpoint.ep_list members chained off the list_head anchored at dwc->gadget->ep_list. Thus when dwc->gadget is freed, the first dwc3_ep in the list now has a dangling prev pointer and likewise for the next pointer of the dwc3_ep at the tail of the list. The dwc3_gadget_free_endpoints() that follows will result in a use-after-free when it calls list_del(). This was caught by enabling KASAN and performing a driver unbind. The recent commit 568262bf5492 (usb: dwc3: core: Add shutdown callback for dwc3) also exposes this as a panic during shutdown. There are a few possibilities to fix this. One could be to perform a list_del() of the gadget->ep_list itself which removes it from the rest of the dwc3_ep chain. Another approach is what this patch does, by splitting up the usb_del_gadget_udc() call into its separate del and put components. This allows dwc3_gadget_free_endpoints() to be called before the gadget is finally freed with usb_put_gadget().
Find out more about CVE-2021-46986 from the MITRE-CVE dictionary and NIST NVD
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| Product Name | Status | Defect | Fixed | Downloads |
|---|---|---|---|---|
| Linux | ||||
| Wind River Linux LTS 17 | Requires LTSS | -- | -- | -- |
| Wind River Linux 8 | Requires LTSS | -- | -- | -- |
| Wind River Linux 9 | Requires LTSS | -- | -- | -- |
| Wind River Linux 7 | Requires LTSS | -- | -- | -- |
| Wind River Linux LTS 21 | Won't Fix | -- | -- | -- |
| Wind River Linux LTS 22 | Not Vulnerable | -- | -- | -- |
| Wind River Linux LTS 18 | Requires LTSS | -- | -- | -- |
| Wind River Linux LTS 19 | Won't Fix | -- | -- | -- |
| Wind River Linux CD release | N/A | -- | -- | -- |
| Wind River Linux 6 | Requires LTSS | -- | -- | -- |
| Wind River Linux LTS 23 | Not Vulnerable | -- | -- | -- |
| VxWorks | ||||
| VxWorks 7 | Not Vulnerable | -- | -- | -- |
| VxWorks 6.9 | Not Vulnerable | -- | -- | -- |
| Helix Virtualization Platform Cert Edition | ||||
| Helix Virtualization Platform Cert Edition | Not Vulnerable | -- | -- | -- |
| Product Name | Status | Defect | Fixed | Downloads |
|---|
