[PATCH] cpufreq: mediatek: guard error paths to avoid kernel panic
Daniel Golle
daniel at makrotopia.org
Thu Mar 23 04:04:23 PDT 2023
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 at mediatek.com>
Suggested-by: Sam Shih <sam.shih at mediatek.com>
Signed-off-by: Daniel Golle <daniel at 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))
+ 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);
--
2.40.0
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