diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 58d3f43cc8bb..17809310d046 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -905,6 +905,11 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
 
 	for (i = 0; i < catlen; i++) {
 		rule += SMK_DIGITLEN;
+		if (rule > data + count) {
+			rc = -EOVERFLOW;
+			goto out;
+		}
+
 		ret = sscanf(rule, "%u", &cat);
 		if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
 			goto out;