Re: [PATCH v2] cpufreq: kryo: Fix possible error code dereference

From: Rafael J. Wysocki
Date: Thu Jun 21 2018 - 09:23:55 EST


On Monday, June 18, 2018 6:55:23 AM CEST Viresh Kumar wrote:
> On 17-06-18, 21:58, ilia.lin@xxxxxxxxx wrote:
> > From: Ilia Lin <ilia.lin@xxxxxxxxx>
> >
> > In event of error returned by the nvmem_cell_read() non-pointer value
> > may be dereferenced. Fix this with error handling.
> > Additionally free the allocated speedbin buffer, as per the API.
> >
> > Fixes: 9ce36edd1a52 (cpufreq: Add Kryo CPU scaling driver)
> > Signed-off-by: Ilia Lin <ilia.lin@xxxxxxxxx>
> > ---
> > drivers/cpufreq/qcom-cpufreq-kryo.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c
> > index d049fe4b80c4..74b9b93d511b 100644
> > --- a/drivers/cpufreq/qcom-cpufreq-kryo.c
> > +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c
> > @@ -115,6 +115,8 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
> >
> > speedbin = nvmem_cell_read(speedbin_nvmem, &len);
> > nvmem_cell_put(speedbin_nvmem);
> > + if (IS_ERR(speedbin))
> > + return PTR_ERR(speedbin);
> >
> > switch (msm8996_version) {
> > case MSM8996_V3:
> > @@ -127,6 +129,7 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
> > BUG();
> > break;
> > }
> > + kfree(speedbin);
> >
> > for_each_possible_cpu(cpu) {
> > cpu_dev = get_cpu_device(cpu);
>
> Ideally this should have been two patches as you were fixing two
> different problems. But anyway, you can go through this time.
>
> Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

Patch applied, thanks!