[PATCH -next] rtc: synqmp: uninitialized variable error

From: Sebin Sebastian
Date: Tue Aug 02 2022 - 21:31:37 EST


fract_tick is uninitialized and can lead to uninitialized read which can
result in any arbitrary value from previous computations. If the code
flow doesnt execute the `if (fract_offset > (tick_mult /
RTC_FR_MAX_TICKS)) { ` block, fract_tick is left uninitialized.
Initializing with zero fixes the issue.

Signed-off-by: Sebin Sebastian <mailmesebin00@xxxxxxxxx>
---
drivers/rtc/rtc-zynqmp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c
index 1dd389b891fe..c9b85c838ebe 100644
--- a/drivers/rtc/rtc-zynqmp.c
+++ b/drivers/rtc/rtc-zynqmp.c
@@ -203,7 +203,7 @@ static int xlnx_rtc_set_offset(struct device *dev, long offset)
struct xlnx_rtc_dev *xrtcdev = dev_get_drvdata(dev);
unsigned long long rtc_ppb = RTC_PPB;
unsigned int tick_mult = do_div(rtc_ppb, xrtcdev->freq);
- unsigned char fract_tick;
+ unsigned char fract_tick = 0;
unsigned int calibval;
short int max_tick;
int fract_offset;
--
2.34.1