https://bugs.gentoo.org/740114
https://git.kernel.org/pub/scm/network/ethtool/ethtool.git/commit/?id=cf12872ebe7d8fac2088e7d2cd5e2a0a5f03499d

--- a/ethtool.c
+++ b/ethtool.c
@@ -3048,10 +3048,11 @@ static int do_sset(struct cmd_context *ctx)
 		struct ethtool_link_usettings *link_usettings;
 
 		link_usettings = do_ioctl_glinksettings(ctx);
-		memset(&link_usettings->deprecated, 0,
-		       sizeof(link_usettings->deprecated));
 		if (link_usettings == NULL)
 			link_usettings = do_ioctl_gset(ctx);
+		else
+			memset(&link_usettings->deprecated, 0,
+			       sizeof(link_usettings->deprecated));
 		if (link_usettings == NULL) {
 			perror("Cannot get current device settings");
 			err = -1;