4.9-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 9e28989d41c0eab57ec0bb156617a8757406ff8a ] When mc13xxx_reg_read() fails, "old_adc0" is uninitialized and will contain random value. Further execution uses "old_adc0" even when mc13xxx_reg_read() fails. The fix checks the return value of mc13xxx_reg_read(), and exits the execution when it fails. Signed-off-by: Kangjie Lu <kjlu@xxxxxxx> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/mfd/mc13xxx-core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/mfd/mc13xxx-core.c b/drivers/mfd/mc13xxx-core.c index d7f54e492aa61..6c16f170529f5 100644 --- a/drivers/mfd/mc13xxx-core.c +++ b/drivers/mfd/mc13xxx-core.c @@ -274,7 +274,9 @@ int mc13xxx_adc_do_conversion(struct mc13xxx *mc13xxx, unsigned int mode, mc13xxx->adcflags |= MC13XXX_ADC_WORKING; - mc13xxx_reg_read(mc13xxx, MC13XXX_ADC0, &old_adc0); + ret = mc13xxx_reg_read(mc13xxx, MC13XXX_ADC0, &old_adc0); + if (ret) + goto out; adc0 = MC13XXX_ADC0_ADINC1 | MC13XXX_ADC0_ADINC2; adc1 = MC13XXX_ADC1_ADEN | MC13XXX_ADC1_ADTRIGIGN | MC13XXX_ADC1_ASC; -- 2.19.1