diff --git a/libmisc/prefix_flag.c b/libmisc/prefix_flag.c
index 6581235e..8ceffd26 100644
--- a/libmisc/prefix_flag.c
+++ b/libmisc/prefix_flag.c
@@ -333,7 +333,7 @@ extern struct group *prefix_getgr_nam_gid(const char *grname)
 	    	&& (gid == (gid_t)gid)) {
 			return prefix_getgrgid ((gid_t) gid);
 		}
-		return prefix_getgrnam (grname);
+		return __gr_dup(prefix_getgrnam (grname));
 	}
 	else
 		return getgr_nam_gid(grname);
diff --git a/src/usermod.c b/src/usermod.c
index e571426f..7355ad31 100644
--- a/src/usermod.c
+++ b/src/usermod.c
@@ -1251,11 +1251,13 @@ static void process_flags (int argc, char **argv)
 		prefix_user_home = xmalloc(len);
 		wlen = snprintf(prefix_user_home, len, "%s/%s", prefix, user_home);
 		assert (wlen == (int) len -1);
+		if (user_newhome) {
+			len = strlen(prefix) + strlen(user_newhome) + 2;
+			prefix_user_newhome = xmalloc(len);
+			wlen = snprintf(prefix_user_newhome, len, "%s/%s", prefix, user_newhome);
+			assert (wlen == (int) len -1);
+		}
 
-		len = strlen(prefix) + strlen(user_newhome) + 2;
-		prefix_user_newhome = xmalloc(len);
-		wlen = snprintf(prefix_user_newhome, len, "%s/%s", prefix, user_newhome);
-		assert (wlen == (int) len -1);
 	}
 	else {
 		prefix_user_home = user_home;