fix undefined behavior with certain left-shift count values (36f93f01) · Commits · e / os / android_system_core

libnetutils/ifc_utils.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -224,6 +224,11 @@ in_addr_t get_ipv4_netmask(int prefix_length)
		{
		in_addr_t mask = 0;

		// C99 (6.5.7): shifts of 32 bits have undefined results
		if (prefix_length == 0) {
		return 0;
		}

		mask = ~mask << (32 - prefix_length);
		mask = htonl(mask);