Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: hif_usb: fix memory leak of remain_skbs hif_dev->remain_skb is allocated and used exclusively in ath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is processed and subsequently freed (in error paths) only during the next call of ath9k_hif_usb_rx_stream(). So, if the urbs are deallocated between those two calls due to the device deinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream() is not called next time and the allocated remain_skb is leaked. Our local Syzkaller instance was able to trigger that. remain_skb makes sense when receiving two consecutive urbs which are logically linked together, i.e. a specific data field from the first skb indicates a cached skb to be allocated, memcpy'd with some data and subsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs deallocation supposedly makes that link irrelevant so we need to free the cached skb in those cases. Fix the leak by introducing a function to explicitly free remain_skb (if it is not NULL) when the rx urbs have been deallocated. remain_skb is NULL when it has not been allocated at all (hif_dev struct is kzalloced) or when it has been processed in next call to ath9k_hif_usb_rx_stream(). Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected fb9987d0f748c983bb795a86f47522313f701a08 before 6719e3797ec52cd144c8a5ba8aaab36674800585; affected fb9987d0f748c983bb795a86f47522313f701a08 before d9899318660791141ea6002fda5577b2c5d7386e; affected fb9987d0f748c983bb795a86f47522313f701a08 before 320d760a35273aa815d58b57e4fd9ba5279a3489; affected fb9987d0f748c983bb795a86f47522313f701a08 before 59073060fe0950c6ecbe12bdc06469dcac62128d; affected fb9987d0f748c983bb795a86f47522313f701a08 before 9b9356a3014123f0ce4b50d9278c1265173150ab; affected fb9987d0f748c983bb795a86f47522313f701a08 before f0931fc8f4b6847c72e170d2326861c0a081d680; affected fb9987d0f748c983bb795a86f47522313f701a08 before 8f02d538878c9b1501f624595eb22ee4e5e0ff84; affected fb9987d0f748c983bb795a86f47522313f701a08 before 7654cc03eb699297130b693ec34e25f77b17c947 |
| Linux / Linux | affected 2.6.35; unaffected 0 before 2.6.35; unaffected 4.19.283 through 4.19.*; unaffected 5.4.243 through 5.4.*; unaffected 5.10.180 through 5.10.*; unaffected 5.15.111 through 5.15.*; unaffected 6.1.28 through 6.1.*; unaffected 6.2.15 through 6.2.*; unaffected 6.3.2 through 6.3.*; unaffected 6.4 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/6719e3797ec52cd144c8a5ba8aaab36674800585
- https://git.kernel.org/stable/c/d9899318660791141ea6002fda5577b2c5d7386e
- https://git.kernel.org/stable/c/320d760a35273aa815d58b57e4fd9ba5279a3489
- https://git.kernel.org/stable/c/59073060fe0950c6ecbe12bdc06469dcac62128d
- https://git.kernel.org/stable/c/9b9356a3014123f0ce4b50d9278c1265173150ab
- https://git.kernel.org/stable/c/f0931fc8f4b6847c72e170d2326861c0a081d680
- https://git.kernel.org/stable/c/8f02d538878c9b1501f624595eb22ee4e5e0ff84
- https://git.kernel.org/stable/c/7654cc03eb699297130b693ec34e25f77b17c947