| Message ID | ZBwyN7NwZ2zqHygr@makrotopia.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | cpufreq: mediatek: guard error paths to avoid kernel panic | expand |
Il 23/03/23 12:04, Daniel Golle ha scritto: > Guard pointer access in error path of mtk_cpu_dvfs_info_init() to > make sure info->proc_reg and info->sram_reg are valid pointers before > accessing them, which would result in kernel panic e.g. in case of > them being set to -EPROBE_DEFER. > > Fixes: 4b9ceb757bbb ("cpufreq: mediatek: Enable clocks and regulators") > Reported-by: Sam Shih <sam.shih@mediatek.com> > Suggested-by: Sam Shih <sam.shih@mediatek.com> > Signed-off-by: Daniel Golle <daniel@makrotopia.org> > --- > drivers/cpufreq/mediatek-cpufreq.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c > index 4466d0c91a6a..980a31ddd0f2 100644 > --- a/drivers/cpufreq/mediatek-cpufreq.c > +++ b/drivers/cpufreq/mediatek-cpufreq.c > @@ -579,10 +579,12 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) > dev_pm_opp_of_cpumask_remove_table(&info->cpus); > > out_free_resources: > - if (regulator_is_enabled(info->proc_reg)) > - regulator_disable(info->proc_reg); > - if (info->sram_reg && regulator_is_enabled(info->sram_reg)) > - regulator_disable(info->sram_reg); > + if (!IS_ERR(info->proc_reg)) > + if (regulator_is_enabled(info->proc_reg)) > + regulator_disable(info->proc_reg); > + if (!IS_ERR(info->sram_reg)) For both, actually, if you suspect that (xxxx)_reg may be NULL, then you should use IS_ERR_OR_NULL() instead... > + if (info->sram_reg && regulator_is_enabled(info->sram_reg)) ...otherwise, here it's useless to check if it's not NULL? Regards, Angelo
diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c index 4466d0c91a6a..980a31ddd0f2 100644 --- a/drivers/cpufreq/mediatek-cpufreq.c +++ b/drivers/cpufreq/mediatek-cpufreq.c @@ -579,10 +579,12 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) dev_pm_opp_of_cpumask_remove_table(&info->cpus); out_free_resources: - if (regulator_is_enabled(info->proc_reg)) - regulator_disable(info->proc_reg); - if (info->sram_reg && regulator_is_enabled(info->sram_reg)) - regulator_disable(info->sram_reg); + if (!IS_ERR(info->proc_reg)) + if (regulator_is_enabled(info->proc_reg)) + regulator_disable(info->proc_reg); + if (!IS_ERR(info->sram_reg)) + if (info->sram_reg && regulator_is_enabled(info->sram_reg)) + regulator_disable(info->sram_reg); if (!IS_ERR(info->proc_reg)) regulator_put(info->proc_reg);
Guard pointer access in error path of mtk_cpu_dvfs_info_init() to make sure info->proc_reg and info->sram_reg are valid pointers before accessing them, which would result in kernel panic e.g. in case of them being set to -EPROBE_DEFER. Fixes: 4b9ceb757bbb ("cpufreq: mediatek: Enable clocks and regulators") Reported-by: Sam Shih <sam.shih@mediatek.com> Suggested-by: Sam Shih <sam.shih@mediatek.com> Signed-off-by: Daniel Golle <daniel@makrotopia.org> --- drivers/cpufreq/mediatek-cpufreq.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)