Activity log
- Created & dismissed (max. allowed matches exceeded) suggestion
usb: gadget: udc: Fix use-after-free in gadget_match_driver
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: udc: Fix use-after-free in gadget_match_driver The udc structure acts as the management structure for the gadget, but their lifecycles are decoupled. A race condition exists where usb_del_gadget() frees the udc memory (e.g., via mode-switch work) while gadget_match_driver() concurrently accesses the freed udc memory (e.g., via configfs), causing a Use-After-Free (UAF) that triggers a NULL pointer dereference when the freed memory is zeroed: [39430.908615][ T1171] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [39430.911397][ T1171] pc : __pi_strcmp+0x20/0x140 [39430.911441][ T1171] lr : gadget_match_driver+0x34/0x60 ... [39430.911890][ T1171] usb_gadget_register_driver_owner+0x50/0xf8 [39430.911910][ T1171] gadget_dev_desc_UDC_store+0xf4/0x140 [39430.931308][ T1171] configfs_write_iter+0xec/0x134 [39430.957058][ T1171] Workqueue: events_freezable __dwc3_set_mode [39430.957287][ T1171] dwc3_gadget_exit+0x34/0x8c [39430.957304][ T1171] __dwc3_set_mode+0xc0/0x664 Fix this by ensuring the udc structure remains allocated until the gadget is released. To achieve this, introduce a new usb_gadget_release() routine to the core. When the gadget is added, usb_add_gadget() stores the gadget's release routine in the udc structure and takes a reference to the udc. When the gadget is released, usb_gadget_release() drops the reference to the udc and then calls the gadget's release routine.
References
Affected products
- <d026f71df141c9b064ff32a78af5391a31ef75c2
- =<7.1.*
- =<6.1.*
- <50eeb8e8a4f389efc91b93cff14a683e714ec194
- =<5.15.*
- <b52476a83d9e12df00765359d728a875b128bef1
- <5.15.212
- <6.12.96
- <67e511d2989eb1c8c588b599ce2fcc6bb8e6f7ea
- <f845852a5a8914277031f47d8de0f350fef52405
- <7a5214dae906d9f58e07bc4995e8181ee74439f4
- <6.6.145
- =<6.6.*
- <7.1.4
- <6.1.178
- =<6.18.*
- =<6.12.*
- <54fa390aae393eb130f307a85562e3001cc39a52
- =<*
- <6.18.39