6.13-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@linaro.org
[ Upstream commit 09c4a610153286cef54d4f0c85398f4e32fc227e ]
The problem is this multiply in tps6594_rtc_set_offset()
tmp = offset * TICKS_PER_HOUR;
The "tmp" variable is an s64 but "offset" is a long in the (-277774)-277774 range. On 32bit systems a long can hold numbers up to approximately two billion. The number of TICKS_PER_HOUR is really large, (32768 * 3600) or roughly a hundred million. When you start multiplying by a hundred million it doesn't take long to overflow the two billion mark.
Probably the safest way to fix this is to change the type of TICKS_PER_HOUR to long long because it's such a large number.
Fixes: 9f67c1e63976 ("rtc: tps6594: Add driver for TPS6594 RTC") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Link: https://lore.kernel.org/r/1074175e-5ecb-4e3d-b721-347d794caa90@stanley.mount... Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/rtc/rtc-tps6594.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/rtc/rtc-tps6594.c b/drivers/rtc/rtc-tps6594.c index e696676341378..7c6246e3f0292 100644 --- a/drivers/rtc/rtc-tps6594.c +++ b/drivers/rtc/rtc-tps6594.c @@ -37,7 +37,7 @@ #define MAX_OFFSET (277774)
// Number of ticks per hour -#define TICKS_PER_HOUR (32768 * 3600) +#define TICKS_PER_HOUR (32768 * 3600LL)
// Multiplier for ppb conversions #define PPB_MULT NANO