Backports v4.19.24

Backports generated by toradex backports 515a1fa55cda2b1d952872e1786857481bd54fcc
against mainline kernel tag v4.19.24

Signed-off-by: Dominik Sliwa <dominik.sliwa@toradex.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/compat/user_namespace.c b/compat/user_namespace.c
new file mode 100644
index 0000000..6d01404
--- /dev/null
+++ b/compat/user_namespace.c
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2012  Luis R. Rodriguez <mcgrof@do-not-panic.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Backport functionality introduced in Linux user_namespace.c
+ */
+
+#include <linux/module.h>
+#include <linux/highuid.h>
+#include <linux/uidgid.h>
+#include <linux/user_namespace.h>
+
+#ifdef CONFIG_USER_NS
+
+kuid_t make_kuid(struct user_namespace *ns, uid_t uid)
+{
+	/* Map the uid to a global kernel uid */
+	return KUIDT_INIT(uid);
+}
+EXPORT_SYMBOL_GPL(make_kuid);
+
+uid_t from_kuid(struct user_namespace *targ, kuid_t kuid)
+{
+	/* Map the uid from a global kernel uid */
+	return __kuid_val(kuid);
+}
+EXPORT_SYMBOL_GPL(from_kuid);
+
+uid_t from_kuid_munged(struct user_namespace *targ, kuid_t kuid)
+{
+	uid_t uid;
+	uid = from_kuid(targ, kuid);
+
+	if (uid == (uid_t) -1)
+		uid = overflowuid;
+	return uid;
+}
+EXPORT_SYMBOL_GPL(from_kuid_munged);
+
+kgid_t make_kgid(struct user_namespace *ns, gid_t gid)
+{
+	/* Map the gid to a global kernel gid */
+	return KGIDT_INIT(gid);
+}
+EXPORT_SYMBOL_GPL(make_kgid);
+
+gid_t from_kgid(struct user_namespace *targ, kgid_t kgid)
+{
+	/* Map the gid from a global kernel gid */
+	return __kgid_val(kgid);
+}
+EXPORT_SYMBOL_GPL(from_kgid);
+
+gid_t from_kgid_munged(struct user_namespace *targ, kgid_t kgid)
+{
+	gid_t gid;
+	gid = from_kgid(targ, kgid);
+
+	if (gid == (gid_t) -1)
+		gid = overflowgid;
+	return gid;
+}
+EXPORT_SYMBOL_GPL(from_kgid_munged);
+
+#endif /* CONFIG_USER_NS */