usb: dwc3: Fix race condition between concurrent dwc3_remove_requests() call paths
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: Fix race condition between concurrent dwc3_remove_requests() call paths
This patch addresses a race condition caused by unsynchronized
execution of multiple call paths invoking `dwc3_remove_requests()`,
leading to premature freeing of USB requests and subsequent crashes.
Three distinct execution paths interact with `dwc3_remove_requests()`:
Path 1:
Triggered via `dwc3_gadget_reset_interrupt()` during USB reset
handling. The call stack includes:
- `dwc3_ep0_reset_state()`
- `dwc3_ep0_stall_and_restart()`
- `dwc3_ep0_out_start()`
- `dwc3_remove_requests()`
- `dwc3_gadget_del_and_unmap_request()`
Path 2:
Also initiated from `dwc3_gadget_reset_interrupt()`, but through
`dwc3_stop_active_transfers()`. The call stack includes:
- `dwc3_stop_active_transfers()`
- `dwc3_remove_requests()`
- `dwc3_gadget_del_and_unmap_request()`
Path 3:
Occurs independently during `adb root` execution, which triggers
USB function unbind and bind operations. The sequence includes:
- `gserial_disconnect()`
- `usb_ep_disable()`
- `dwc3_gadget_ep_disable()`
- `dwc3_remove_requests()` with `-ESHUTDOWN` status
Path 3 operates asynchronously and lacks synchronization with Paths
1 and 2. When Path 3 completes, it disables endpoints and frees 'out'
requests. If Paths 1 or 2 are still processing these requests,
accessing freed memory leads to a crash due to use-after-free conditions.
To fix this added check for request completion and skip processing
if already completed and added the request status for ep0 while queue.
CVE 정보
EPSS
EPSS는 취약점이 악용될 가능성을 예측하는 점수 모델입니다.
EPSS 점수
EPSS 모델은 0과 1(0~100%) 사이의 확률 점수를 생성합니다. 점수가 높을수록 취약점이 악용될 가능성이 높습니다.
날짜
EPSS V0
EPSS V1
EPSS V2 (> 2022-02-04)
EPSS V3 (> 2025-03-07)
EPSS V4 (> 2025-03-17)
2025-12-17
–
–
–
–
0.02%
2025-12-22
–
–
–
–
0.03%
2025-12-25
–
–
–
–
0.03%
2025-12-27
–
–
–
–
0.03%
2025-12-28
–
–
–
–
0.03%
2025-12-29
–
–
–
–
0.03%
2025-12-31
–
–
–
–
0.03%
2026-01-04
–
–
–
–
0.03%
2026-01-08
–
–
–
–
0.03%
2026-01-12
–
–
–
–
0.03%
2026-01-16
–
–
–
–
0.03%
2026-01-17
–
–
–
–
0.03%
2026-01-18
–
–
–
–
0.08%
2026-02-22
–
–
–
–
0.07%
2026-04-26
–
–
–
–
0.09%
2026-05-17
–
–
–
–
0.06%
2026-05-31
–
–
–
–
0.08%
EPSS 백분위수
백분위수는 EPSS 점수에 따라 CVE의 순위를 매기는 데 사용됩니다. 예를 들어 EPSS 점수 기준 95번째 백분위수의 CVE는 다른 CVE의 95%보다 악용될 가능성이 높습니다.