Re: [PATCH v3] mac802154: Fix potential RCU dereference issue in mac802154_scan_worker

[Przemek Kitszel]

On 9/24/24 08:58, Jiawei Ye wrote:
> In the `mac802154_scan_worker` function, the `scan_req->type` field was
> accessed after the RCU read-side critical section was unlocked. According
> to RCU usage rules, this is illegal and can lead to unpredictable
> behavior, such as accessing memory that has been updated or causing
> use-after-free issues.
>
> This possible bug was identified using a static analysis tool developed
> by myself, specifically designed to detect RCU-related issues.
>
> To address this, the `scan_req->type` value is now stored in a local
> variable `scan_req_type` while still within the RCU read-side critical
> section. The `scan_req_type` is then used after the RCU lock is released,
> ensuring that the type value is safely accessed without violating RCU
> rules.
>
> Fixes: e2c3e6f53a7a ("mac802154: Handle active scanning")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Jiawei Ye <jiawei.ye@xxxxxxxxxxx>
> Acked-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>