From ebf2b16d09b087a183c3ba6ee40ee00d094fb258 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Sat, 28 Jun 2025 21:28:54 +0300
Subject: [PATCH] Kernel: Implement chown to ext2 and tmpfs

---
 kernel/include/kernel/FS/Ext2/Inode.h  |  1 +
 kernel/include/kernel/FS/TmpFS/Inode.h |  1 +
 kernel/kernel/FS/Ext2/Inode.cpp        | 20 ++++++++++++++++++++
 kernel/kernel/FS/TmpFS/Inode.cpp       |  7 +++++++
 4 files changed, 29 insertions(+)

diff --git a/kernel/include/kernel/FS/Ext2/Inode.h b/kernel/include/kernel/FS/Ext2/Inode.h
index d84851bd..bfa07c25 100644
--- a/kernel/include/kernel/FS/Ext2/Inode.h
+++ b/kernel/include/kernel/FS/Ext2/Inode.h
@@ -46,6 +46,7 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override;
 		virtual BAN::ErrorOr<void> truncate_impl(size_t) override;
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
+		virtual BAN::ErrorOr<void> chown_impl(uid_t, gid_t) override;
 		virtual BAN::ErrorOr<void> utimens_impl(const timespec[2]) override;
 		virtual BAN::ErrorOr<void> fsync_impl() override;
 
diff --git a/kernel/include/kernel/FS/TmpFS/Inode.h b/kernel/include/kernel/FS/TmpFS/Inode.h
index eaffad03..76d17c24 100644
--- a/kernel/include/kernel/FS/TmpFS/Inode.h
+++ b/kernel/include/kernel/FS/TmpFS/Inode.h
@@ -48,6 +48,7 @@ namespace Kernel
 		TmpInode(TmpFileSystem&, ino_t, const TmpInodeInfo&);
 
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
+		virtual BAN::ErrorOr<void> chown_impl(uid_t, gid_t) override;
 		virtual BAN::ErrorOr<void> utimens_impl(const timespec[2]) override;
 		virtual BAN::ErrorOr<void> fsync_impl() override { return {}; }
 
diff --git a/kernel/kernel/FS/Ext2/Inode.cpp b/kernel/kernel/FS/Ext2/Inode.cpp
index c7560433..0dcdf75d 100644
--- a/kernel/kernel/FS/Ext2/Inode.cpp
+++ b/kernel/kernel/FS/Ext2/Inode.cpp
@@ -289,6 +289,26 @@ namespace Kernel
 		return {};
 	}
 
+	BAN::ErrorOr<void> Ext2Inode::chown_impl(uid_t uid, gid_t gid)
+	{
+		if (m_inode.uid == uid && m_inode.gid == gid)
+			return {};
+
+		const auto old_uid = m_inode.uid;
+		const auto old_gid = m_inode.gid;
+
+		m_inode.uid = uid;
+		m_inode.gid = gid;
+		if (auto ret = sync(); ret.is_error())
+		{
+			m_inode.uid = old_uid;
+			m_inode.gid = old_gid;
+			return ret.release_error();
+		}
+
+		return {};
+	}
+
 	BAN::ErrorOr<void> Ext2Inode::utimens_impl(const timespec times[2])
 	{
 		const uint32_t old_times[2] {
diff --git a/kernel/kernel/FS/TmpFS/Inode.cpp b/kernel/kernel/FS/TmpFS/Inode.cpp
index 78e46cb8..c28ba0e1 100644
--- a/kernel/kernel/FS/TmpFS/Inode.cpp
+++ b/kernel/kernel/FS/TmpFS/Inode.cpp
@@ -100,6 +100,13 @@ namespace Kernel
 		return {};
 	}
 
+	BAN::ErrorOr<void> TmpInode::chown_impl(uid_t new_uid, gid_t new_gid)
+	{
+		m_inode_info.uid = new_uid;
+		m_inode_info.gid = new_gid;
+		return {};
+	}
+
 	BAN::ErrorOr<void> TmpInode::utimens_impl(const timespec times[2])
 	{
 		if (times[0].tv_nsec != UTIME_OMIT)