From 8ee3a5e09ecfba40a3b53af0b3a7bd08424479e5 Mon Sep 17 00:00:00 2001
From: Ralf Donau <ruelle@volleyballschlaeger.de>
Date: Thu, 8 Jul 2021 20:29:46 +0200
Subject: [PATCH] Kernel: Logic fix in the pledge syscall

Pledge should check m_has_promises. Calling pledge("", nullptr)
does not fail on an already pledged process anymore.
---
 Kernel/Syscalls/pledge.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Kernel/Syscalls/pledge.cpp b/Kernel/Syscalls/pledge.cpp
index b03a011598..ae9e7d2d71 100644
--- a/Kernel/Syscalls/pledge.cpp
+++ b/Kernel/Syscalls/pledge.cpp
@@ -53,7 +53,7 @@ KResultOr<FlatPtr> Process::sys$pledge(Userspace<const Syscall::SC_pledge_params
         u32 new_promises = 0;
         if (!parse_pledge(promises, new_promises))
             return EINVAL;
-        if (m_promises && (!new_promises || new_promises & ~m_promises))
+        if (m_has_promises && (new_promises & ~m_promises))
             return EPERM;
 
         m_has_promises = true;
@@ -64,7 +64,7 @@ KResultOr<FlatPtr> Process::sys$pledge(Userspace<const Syscall::SC_pledge_params
         u32 new_execpromises = 0;
         if (!parse_pledge(execpromises, new_execpromises))
             return EINVAL;
-        if (m_execpromises && (!new_execpromises || new_execpromises & ~m_execpromises))
+        if (m_has_execpromises && (new_execpromises & ~m_execpromises))
             return EPERM;
         m_has_execpromises = true;
         m_execpromises = new_execpromises;