Fix netd crash on gethostbyname(NULL) and add a regression test (c0d8ada5) · Commits · e / os / android_packages_modules_DnsResolver

gethnamaddr.cpp

+4 −1

Original line number	Diff line number	Diff line
		@@ -388,8 +388,11 @@ nospc:
		int resolv_gethostbyname(const char* name, int af, hostent* hp, char* buf, size_t buflen,
		const android_net_context* netcontext, hostent** result,
		NetworkDnsEventReported* event) {
		getnamaddr info;
		if (name == nullptr \|\| hp == nullptr) {
		return EAI_SYSTEM;
		}

		getnamaddr info;
		ResState res;
		res_init(&res, netcontext, event);

+14 −1

Original line number	Diff line number	Diff line
		@@ -393,7 +393,7 @@ TEST_F(ResolverTest, GetHostByName) {
		result = gethostbyname("nonexistent");
		EXPECT_EQ(1U, GetNumQueriesForType(dns, ns_type::ns_t_a, nonexistent_host_name));
		ASSERT_TRUE(result == nullptr);
		ASSERT_EQ(HOST_NOT_FOUND, h_errno);
		EXPECT_EQ(HOST_NOT_FOUND, h_errno);

		dns.clearQueries();
		result = gethostbyname("hello");
		@@ -405,6 +405,19 @@ TEST_F(ResolverTest, GetHostByName) {
		EXPECT_TRUE(result->h_addr_list[1] == nullptr);
		}

		TEST_F(ResolverTest, GetHostByName_NULL) {
		// Most libc implementations would just crash on gethostbyname(NULL). Instead, Bionic
		// serializes the null argument over dnsproxyd, causing the server-side to crash!
		// This is a regression test.
		const char* const testcases[] = {nullptr, "", "^"};
		for (const char* name : testcases) {
		SCOPED_TRACE(fmt::format("gethostbyname({})", name ? name : "NULL"));
		const hostent* result = gethostbyname(name);
		EXPECT_TRUE(result == nullptr);
		EXPECT_EQ(HOST_NOT_FOUND, h_errno);
		}
		}

		TEST_F(ResolverTest, GetHostByName_cnames) {
		constexpr char host_name[] = "host.example.com.";
		size_t cnamecount = 0;