diff --git a/src/dns/nm-dns-manager.c b/src/dns/nm-dns-manager.c
index c4402d5dc5..0266c0708f 100644
--- a/src/dns/nm-dns-manager.c
+++ b/src/dns/nm-dns-manager.c
@@ -594,10 +594,39 @@ create_resolv_conf (const char *const*searches,
 	g_string_append (str, "# Generated by NetworkManager\n");
 
 	if (searches && searches[0]) {
+		gsize search_base_idx;
+
 		g_string_append (str, "search");
+		search_base_idx = str->len;
+
 		for (i = 0; searches[i]; i++) {
+			const char *s = searches[i];
+			gsize l = strlen (s);
+
+			if (   l == 0
+			    || NM_STRCHAR_ANY (s, ch, NM_IN_SET (ch, ' ', '\t', '\n'))) {
+				/* there should be no such characters in the search entry. Also,
+				 * because glibc parser would treat them as line/word separator.
+				 *
+				 * Skip the value silently. */
+				continue;
+			}
+
+			if (search_base_idx > 0) {
+				if (str->len - search_base_idx + 1 + l > 254) {
+					/* this entry crosses the 256 character boundery. Older glibc versions
+					 * would truncate the entry at this point.
+					 *
+					 * Fill the line with spaces to cross the 256 char boundary and continue
+					 * afterwards. This way, the truncation happens between two search entries. */
+					while (str->len - search_base_idx < 257)
+						g_string_append_c (str, ' ');
+					search_base_idx = 0;
+				}
+			}
+
 			g_string_append_c (str, ' ');
-			g_string_append (str, searches[i]);
+			g_string_append_len (str, s, l);
 		}
 		g_string_append_c (str, '\n');
 	}
diff --git a/src/tests/test-general.c b/src/tests/test-general.c
index 34b183a65d..01d964322c 100644
--- a/src/tests/test-general.c
+++ b/src/tests/test-general.c
@@ -1884,7 +1884,7 @@ test_dns_create_resolv_conf (void)
 	          NULL,
 	          NULL,
 	          "# Generated by NetworkManager\n"
-	          "search a2x456789.b2x456789.c2x456789.d2x456789.e2x456789.f2x456789.g2x456789.h2x456789.i2x456789.j2x4567890 a2y456789.b2y456789.c2y456789.d2y456789.e2y456789.f2y456789.g2y456789.h2y456789.i2y456789.j2y4567890 a2z456789.b2z456789.c2z456789.d2z456789.e2z456789.f2z456789.g2z456789.h2z456789.i2z456789.j2z4567890\n"
+	          "search a2x456789.b2x456789.c2x456789.d2x456789.e2x456789.f2x456789.g2x456789.h2x456789.i2x456789.j2x4567890 a2y456789.b2y456789.c2y456789.d2y456789.e2y456789.f2y456789.g2y456789.h2y456789.i2y456789.j2y4567890                                                        a2z456789.b2z456789.c2z456789.d2z456789.e2z456789.f2z456789.g2z456789.h2z456789.i2z456789.j2z4567890\n"
 	          "");
 
 }