PM / devfreq: exynos-bus: Fix NULL pointer dereference

[PATCH v2] PM / devfreq: exynos-bus: Fix NULL pointer dereference

Posted by Christian Marangi 3 years, 9 months ago

Fix exynos-bus NULL pointer dereference by correctly using the local
generated freq_table to output the debug values instead of using the
profile freq_table that is not used in the driver.

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fixes: b5d281f6c16d ("PM / devfreq: Rework freq_table to be local to devfreq struct")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/exynos-bus.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
index b5615e667e31..79725bbb4bb0 100644
--- a/drivers/devfreq/exynos-bus.c
+++ b/drivers/devfreq/exynos-bus.c
@@ -447,9 +447,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
 		}
 	}
 
-	max_state = bus->devfreq->profile->max_state;
-	min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
-	max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
+	max_state = bus->devfreq->max_state;
+	min_freq = (bus->devfreq->freq_table[0] / 1000);
+	max_freq = (bus->devfreq->freq_table[max_state - 1] / 1000);
 	pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
 			dev_name(dev), min_freq, max_freq);
 
-- 
2.36.1

Re: [PATCH v2] PM / devfreq: exynos-bus: Fix NULL pointer dereference

Posted by Chanwoo Choi 3 years, 9 months ago

Dear Rafael,

The pull request[1] has an  issue for exynos-bus.c devfreq driver
and then fixed it by this patch.

If possible, could you please apply this patch to linux-pm.git
directly for 5.19-rc5?

[1] "[GIT,PULL] devfreq fixes for 5.19-rc5"
- https://patchwork.kernel.org/project/linux-pm/patch/03056170-6501-3f4d-0331-37866d12330e@gmail.com/

Best Regards,
Chanwoo Choi

On Fri, Jul 1, 2022 at 10:45 PM Christian Marangi <ansuelsmth@gmail.com> wrote:
>
> Fix exynos-bus NULL pointer dereference by correctly using the local
> generated freq_table to output the debug values instead of using the
> profile freq_table that is not used in the driver.
>
> Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Fixes: b5d281f6c16d ("PM / devfreq: Rework freq_table to be local to devfreq struct")
> Cc: stable@vger.kernel.org
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
> ---
>  drivers/devfreq/exynos-bus.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index b5615e667e31..79725bbb4bb0 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -447,9 +447,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
>                 }
>         }
>
> -       max_state = bus->devfreq->profile->max_state;
> -       min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
> -       max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
> +       max_state = bus->devfreq->max_state;
> +       min_freq = (bus->devfreq->freq_table[0] / 1000);
> +       max_freq = (bus->devfreq->freq_table[max_state - 1] / 1000);
>         pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
>                         dev_name(dev), min_freq, max_freq);
>
> --
> 2.36.1
>