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authorJakub Kicinski <kuba@kernel.org>2021-01-14 18:34:50 -0800
committerJakub Kicinski <kuba@kernel.org>2021-01-14 18:34:50 -0800
commit1d9f03c0a15fa01aa14fb295cbc1236403fceb0b (patch)
tree2161a4e17f383a14e1e235e2deed7142733aca9b /drivers/hwmon/pwm-fan.c
parente4abfd88c78105069eef627e04ef9413746bab7b (diff)
parent146620506274bd24d52fb1c589110a30eed8240b (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/hwmon/pwm-fan.c')
-rw-r--r--drivers/hwmon/pwm-fan.c12
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 777439f48c14..111a91dc6b79 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -334,8 +334,18 @@ static int pwm_fan_probe(struct platform_device *pdev)
ctx->pwm_value = MAX_PWM;
- /* Set duty cycle to maximum allowed and enable PWM output */
pwm_init_state(ctx->pwm, &state);
+ /*
+ * __set_pwm assumes that MAX_PWM * (period - 1) fits into an unsigned
+ * long. Check this here to prevent the fan running at a too low
+ * frequency.
+ */
+ if (state.period > ULONG_MAX / MAX_PWM + 1) {
+ dev_err(dev, "Configured period too big\n");
+ return -EINVAL;
+ }
+
+ /* Set duty cycle to maximum allowed and enable PWM output */
state.duty_cycle = ctx->pwm->args.period - 1;
state.enabled = true;