OK, I'll include a single security check. Can't have uid=0 or gid=0.

1 files changed, 4 insertions, 0 deletions

diff --git a/main.c b/main.c
index 7af7c55..8d07953 100644
--- a/main.c
+++ b/main.c
@@ -43,6 +43,10 @@ int main( int argc, char *argv[] ) {
   };
   assert( grouppw != NULL );
 
+  // literally the only security check
+  assert( grouppw->gr_gid != 0 );
+  assert( userpw->pw_uid != 0 );
+
   if ( setgroups( 0, NULL ) != 0 )
     assert_perror( errno );