diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
index b352df4cd3f9..f329263f33aa 100644
--- a/drivers/ptp/ptp_private.h
+++ b/drivers/ptp/ptp_private.h
@@ -22,6 +22,7 @@
 #define PTP_MAX_TIMESTAMPS 128
 #define PTP_BUF_TIMESTAMPS 30
 #define PTP_DEFAULT_MAX_VCLOCKS 20
+#define PTP_MAX_VCLOCKS_LIMIT (KMALLOC_MAX_SIZE/(sizeof(int)))
 #define PTP_MAX_CHANNELS 2048
 
 enum {
diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index 6b1b8f57cd95..200eaf500696 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -284,7 +284,7 @@ static ssize_t max_vclocks_store(struct device *dev,
 	size_t size;
 	u32 max;
 
-	if (kstrtou32(buf, 0, &max) || max == 0)
+	if (kstrtou32(buf, 0, &max) || max == 0 || max > PTP_MAX_VCLOCKS_LIMIT)
 		return -EINVAL;
 
 	if (max == ptp->max_vclocks)