Description (CNA)
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().
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected e81a7018d93a7de31a3f121c9a7eecd0a5ec58b0 before 1ea775021282d90e1d08d696b7ab54aa75d688e5; affected e81a7018d93a7de31a3f121c9a7eecd0a5ec58b0 before bc0cdd72493236fb72b390ad38ce581e353c143c; affected e81a7018d93a7de31a3f121c9a7eecd0a5ec58b0 before b4b8e9601d7ee8806d2687f081a42485d27674a1; affected e81a7018d93a7de31a3f121c9a7eecd0a5ec58b0 before bb9c74a5bd1462499fe5ccb1e3c5ac40dcfa9139 |
| Linux / Linux | affected 5.10; unaffected 0 before 5.10; unaffected 5.10.38 through 5.10.*; unaffected 5.11.22 through 5.11.*; unaffected 5.12.5 through 5.12.*; unaffected 5.13 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/1ea775021282d90e1d08d696b7ab54aa75d688e5
- https://git.kernel.org/stable/c/bc0cdd72493236fb72b390ad38ce581e353c143c
- https://git.kernel.org/stable/c/b4b8e9601d7ee8806d2687f081a42485d27674a1
- https://git.kernel.org/stable/c/bb9c74a5bd1462499fe5ccb1e3c5ac40dcfa9139
ADP enrichment
No English description supplied.
No English description supplied.
No references supplied.