dns_resolver: Do not accept domain names longer than 255 chars

According to RFC1035 "[...] the total length of a domain name (i.e., label octets and label length octets) is restricted to 255 octets or less." Signed-off-by: Manuel Schölling <manuel.schoelling@gmx.de> Signed-off-by: David S. Miller <davem@davemloft.net>
mariux64 · Jun 5, 2014 · 9638f67 · 9638f67
1 parent 555878b
commit 9638f67
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
@@ -93,8 +93,8 @@ int dns_query(const char *type, const char *name, size_t namelen,
 	}
 
 	if (!namelen)
-		namelen = strlen(name);
-	if (namelen < 3)
+		namelen = strnlen(name, 256);
+	if (namelen < 3 || namelen > 255)
 		return -EINVAL;
 	desclen += namelen + 1;