From 14cfb1b990b4068f33ebd9b2a1d85bdd0e1e3921 Mon Sep 17 00:00:00 2001
From: Nicholas Andrew <BOBtheBlinker@gMail.com>
Date: Fri, 18 Sep 2026 19:56:56 -0400
Subject: [PATCH] fs: add KernelSU umount compatibility helpers

---
 fs/namespace.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/fs/namespace.c b/fs/namespace.c
index 176bccdf6f30..baa802d6cba3 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1756,6 +1756,43 @@ SYSCALL_DEFINE1(oldumount, char __user *, name)
 
 #endif
 
+
+static int can_umount(const struct path *path, int flags)
+{
+	struct mount *mnt = real_mount(path->mnt);
+
+	if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW))
+		return -EINVAL;
+	if (!may_mount())
+		return -EPERM;
+	if (path->dentry != path->mnt->mnt_root)
+		return -EINVAL;
+	if (!check_mnt(mnt))
+		return -EINVAL;
+	if (mnt->mnt.mnt_flags & MNT_LOCKED)
+		return -EINVAL;
+	if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	return 0;
+}
+
+
+int path_umount(struct path *path, int flags)
+{
+	struct mount *mnt = real_mount(path->mnt);
+	int ret;
+
+	ret = can_umount(path, flags);
+	if (!ret)
+		ret = do_umount(mnt, flags);
+
+	dput(path->dentry);
+	mntput_no_expire(mnt);
+
+	return ret;
+}
+
 static bool is_mnt_ns_file(struct dentry *dentry)
 {
 	/* Is this a proxy for a mount namespace? */