From 24b71d1170fe887806ba538398c5c75ae801d96d Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Wed, 6 Dec 2023 18:14:27 +0200
Subject: [PATCH] Kernel: Appreciate setuid and setgid bits executables

---
 LibELF/LibELF/LoadableELF.cpp       | 8 ++++++++
 LibELF/include/LibELF/LoadableELF.h | 3 +++
 kernel/kernel/Process.cpp           | 1 +
 3 files changed, 12 insertions(+)

diff --git a/LibELF/LibELF/LoadableELF.cpp b/LibELF/LibELF/LoadableELF.cpp
index 20d19b8a07..ebdb037afb 100644
--- a/LibELF/LibELF/LoadableELF.cpp
+++ b/LibELF/LibELF/LoadableELF.cpp
@@ -203,6 +203,14 @@ namespace LibELF
 		m_loaded = true;
 	}
 
+	void LoadableELF::update_suid_sgid(Kernel::Credentials& credentials)
+	{
+		if (m_inode->mode().mode & +Inode::Mode::ISUID)
+			credentials.set_euid(m_inode->uid());
+		if (m_inode->mode().mode & +Inode::Mode::ISGID)
+			credentials.set_egid(m_inode->gid());
+	}
+
 	BAN::ErrorOr<void> LoadableELF::load_page_to_memory(vaddr_t address)
 	{
 		for (const auto& program_header : m_program_headers)
diff --git a/LibELF/include/LibELF/LoadableELF.h b/LibELF/include/LibELF/LoadableELF.h
index d4733fa032..cd1431192b 100644
--- a/LibELF/include/LibELF/LoadableELF.h
+++ b/LibELF/include/LibELF/LoadableELF.h
@@ -7,6 +7,7 @@
 #include <BAN/UniqPtr.h>
 #include <BAN/Vector.h>
 
+#include <kernel/Credentials.h>
 #include <kernel/FS/Inode.h>
 #include <kernel/Memory/PageTable.h>
 
@@ -30,6 +31,8 @@ namespace LibELF
 		bool is_address_space_free() const;
 		void reserve_address_space();
 
+		void update_suid_sgid(Kernel::Credentials&);
+
 		BAN::ErrorOr<void> load_page_to_memory(Kernel::vaddr_t address);
 
 		BAN::ErrorOr<BAN::UniqPtr<LoadableELF>> clone(Kernel::PageTable&);
diff --git a/kernel/kernel/Process.cpp b/kernel/kernel/Process.cpp
index 45e420fa46..664459127c 100644
--- a/kernel/kernel/Process.cpp
+++ b/kernel/kernel/Process.cpp
@@ -474,6 +474,7 @@ namespace Kernel
 				MUST(sys_kill(pid(), SIGKILL));
 			}
 			m_loadable_elf->reserve_address_space();
+			m_loadable_elf->update_suid_sgid(m_credentials);
 			m_userspace_info.entry = m_loadable_elf->entry_point();
 
 			for (size_t i = 0; i < sizeof(m_signal_handlers) / sizeof(*m_signal_handlers); i++)