Messages in this thread Patch in this message | | | From | Lei YU <> | Subject | [PATCH] hwmon (occ): Fix division by zero issue | Date | Thu, 11 Jul 2019 10:44:48 +0800 |
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The code in occ_get_powr_avg() invokes div64_u64() without checking the divisor. In case the divisor is zero, kernel gets an "Division by zero in kernel" error.
Check the divisor and make it return 0 if the divisor is 0.
Signed-off-by: Lei YU <mine260309@gmail.com> Reviewed-by: Eddie James <eajames@linux.ibm.com> --- drivers/hwmon/occ/common.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c index 13a6290..f02aa40 100644 --- a/drivers/hwmon/occ/common.c +++ b/drivers/hwmon/occ/common.c @@ -402,8 +402,10 @@ static ssize_t occ_show_power_1(struct device *dev, static u64 occ_get_powr_avg(u64 *accum, u32 *samples) { - return div64_u64(get_unaligned_be64(accum) * 1000000ULL, - get_unaligned_be32(samples)); + u64 divisor = get_unaligned_be32(samples); + + return (divisor == 0) ? 0 : + div64_u64(get_unaligned_be64(accum) * 1000000ULL, divisor); } static ssize_t occ_show_power_2(struct device *dev, -- 2.7.4
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