1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index cf98a5d8358e..b6d35f50e404 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -35,6 +35,7 @@
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
 #include <linux/mod_devicetable.h>
+#include <linux/log2.h>
 
 /* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
 #include <asm-generic/rtc.h>
@@ -384,6 +385,8 @@ static int cmos_irq_set_freq(struct device *dev, int freq)
         if (!is_valid_irq(cmos->irq))
                 return -ENXIO;
 
+        if (!is_power_of_2(freq))
+                return -EINVAL;
         /* 0 = no irqs; 1 = 2^15 Hz ... 15 = 2^0 Hz */
         f = ffs(freq);
         if (f-- > 16)