Re: [PATCH] kasan: make report_lock a raw spinlock

From: Andrew Morton
Date: Fri Nov 22 2024 - 01:28:25 EST


On Tue, 19 Nov 2024 13:02:34 -0800 Jared Kangas <jkangas@xxxxxxxxxx> wrote:

> If PREEMPT_RT is enabled, report_lock is a sleeping spinlock and must
> not be locked when IRQs are disabled. However, KASAN reports may be
> triggered in such contexts. For example:
>
> char *s = kzalloc(1, GFP_KERNEL);
> kfree(s);
> local_irq_disable();
> char c = *s; /* KASAN report here leads to spin_lock() */
> local_irq_enable();
>
> Make report_spinlock a raw spinlock to prevent rescheduling when
> PREEMPT_RT is enabled.

So I assume we want this backported into 6.12.x?

If so, please help us identify a suitable Fixes: commit.