Re: [PATCH] workqueue: Add a new flag to spot the potential UAF error

From: Lai Jiangshan
Date: Wed Dec 14 2022 - 02:17:06 EST


On Tue, Dec 13, 2022 at 12:40 PM Richard Clark
<richard.xnu.clark@xxxxxxxxx> wrote:
>
> Currently if the user queues a new work item unintentionally
> into a wq after the destroy_workqueue(wq), the work still can
> be queued and scheduled without any noticeable kernel message
> before the end of a RCU grace period.
>
> As a debug-aid facility, this commit adds a new flag
> __WQ_DESTROYING to spot that issue by triggering a kernel WARN
> message.
>
> Signed-off-by: Richard Clark <richard.xnu.clark@xxxxxxxxx>

Reviewed-by: Lai Jiangshan <jiangshanlai@xxxxxxxxx>