From 5abc30e0577832030aa45574d79727ba1c58b788 Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Sat, 4 Jan 2020 13:47:54 +0100
Subject: [PATCH] Kernel: Allow setgroups() to drop all groups with nullptr

Previously we'd EFAULT for setgroups(0, nullptr), but we can just as
well tolerate it if someone wants to drop groups without a pointer.
---
 Kernel/Process.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp
index 62d5cccf0b..7d7af10da1 100644
--- a/Kernel/Process.cpp
+++ b/Kernel/Process.cpp
@@ -2270,7 +2270,7 @@ int Process::sys$setgroups(ssize_t count, const gid_t* gids)
         return -EINVAL;
     if (!is_superuser())
         return -EPERM;
-    if (!validate_read(gids, count))
+    if (count && !validate_read(gids, count))
         return -EFAULT;
     m_extra_gids.clear();
     for (int i = 0; i < count; ++i) {