Re: [PATCH v4] irqchip/gic-v3-its: Fix potential race condition in its_vlpi_prop_update()

From: Marc Zyngier
Date: Fri May 31 2024 - 13:40:10 EST


On Fri, 31 May 2024 17:21:44 +0100,
Hagar Hemdan <hagarhem@xxxxxxxxxx> wrote:
>
> its_vlpi_prop_update() calls lpi_write_config() which obtains the
> mapping information for a VLPI without lock held. So it could race
> with its_vlpi_unmap().
> Since all calls from its_irq_set_vcpu_affinity() require the same
> lock to be held. So instead of peppering the locking all over the
> place, we hoist the locking into its_irq_set_vcpu_affinity().

This looks odd. Maybe something along the lines of:

"Since all calls from its_irq_set_vcpu_affinity() require the same
lock to be held, hoist the locking there instead of peppering it over
the place."

>
> This bug was discovered using Coverity Static Analysis
> Security Testing (SAST) by Synopsys, Inc.
>
> Fixes: 015ec0386ab6 ("irqchip/gic-v3-its: Add VLPI configuration handling")
> Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
> Signed-off-by: Hagar Hemdan <hagarhem@xxxxxxxxxx>

With the above addressed,

Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx

Thomas, can you please queue it at your earliest convenience?

Thanks,

M.

--
Without deviation from the norm, progress is not possible.