diff --git a/fs/proc/base.c b/fs/proc/base.c
index 138cff4b05dd7e04f6bf788f5f14bc5746840295..acd1960c28a293c57c2738ec836b683226f6f34c 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2991,6 +2991,11 @@ static int proc_gid_map_open(struct inode *inode, struct file *file)
return proc_id_map_open(inode, file, &proc_gid_seq_operations);
}
+static int proc_projid_map_open(struct inode *inode, struct file *file)
+{
+ return proc_id_map_open(inode, file, &proc_projid_seq_operations);
+}
+
static const struct file_operations proc_uid_map_operations = {
.open = proc_uid_map_open,
.write = proc_uid_map_write,
@@ -3006,6 +3011,14 @@ static const struct file_operations proc_gid_map_operations = {
.llseek = seq_lseek,
.release = proc_id_map_release,
};
+
+static const struct file_operations proc_projid_map_operations = {
+ .open = proc_projid_map_open,
+ .write = proc_projid_map_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = proc_id_map_release,
+};
#endif /* CONFIG_USER_NS */
static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
@@ -3113,6 +3126,7 @@ static const struct pid_entry tgid_base_stuff[] = {
#ifdef CONFIG_USER_NS
REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
+ REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
#endif
};
@@ -3476,6 +3490,7 @@ static const struct pid_entry tid_base_stuff[] = {
#ifdef CONFIG_USER_NS
REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
+ REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
#endif
};
diff --git a/include/linux/projid.h b/include/linux/projid.h
new file mode 100644
index 0000000000000000000000000000000000000000..36517b95be5cda9ed2605a2bca4e120be3d1e123
--- /dev/null
+++ b/include/linux/projid.h
@@ -0,0 +1,104 @@
+#ifndef _LINUX_PROJID_H
+#define _LINUX_PROJID_H
+
+/*
+ * A set of types for the internal kernel types representing project ids.
+ *
+ * The types defined in this header allow distinguishing which project ids in
+ * the kernel are values used by userspace and which project id values are
+ * the internal kernel values. With the addition of user namespaces the values
+ * can be different. Using the type system makes it possible for the compiler
+ * to detect when we overlook these differences.
+ *
+ */
+#include <linux/types.h>
+
+struct user_namespace;
+extern struct user_namespace init_user_ns;
+
+typedef __kernel_uid32_t projid_t;
+
+#ifdef CONFIG_UIDGID_STRICT_TYPE_CHECKS
+
+typedef struct {
+ projid_t val;
+} kprojid_t;
+
+static inline projid_t __kprojid_val(kprojid_t projid)
+{
+ return projid.val;
+}
+
+#define KPROJIDT_INIT(value) (kprojid_t){ value }
+
+#else
+
+typedef projid_t kprojid_t;
+
+static inline projid_t __kprojid_val(kprojid_t projid)
+{
+ return projid;
+}
+
+#define KPROJIDT_INIT(value) ((kprojid_t) value )
+
+#endif
+
+#define INVALID_PROJID KPROJIDT_INIT(-1)
+#define OVERFLOW_PROJID 65534
+
+static inline bool projid_eq(kprojid_t left, kprojid_t right)
+{
+ return __kprojid_val(left) == __kprojid_val(right);
+}
+
+static inline bool projid_lt(kprojid_t left, kprojid_t right)
+{
+ return __kprojid_val(left) < __kprojid_val(right);
+}
+
+static inline bool projid_valid(kprojid_t projid)
+{
+ return !projid_eq(projid, INVALID_PROJID);
+}
+
+#ifdef CONFIG_USER_NS
+
+extern kprojid_t make_kprojid(struct user_namespace *from, projid_t projid);
+
+extern projid_t from_kprojid(struct user_namespace *to, kprojid_t projid);
+extern projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t projid);
+
+static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
+{
+ return from_kprojid(ns, projid) != (projid_t)-1;
+}
+
+#else
+
+static inline kprojid_t make_kprojid(struct user_namespace *from, projid_t projid)
+{
+ return KPROJIDT_INIT(projid);
+}
+
+static inline projid_t from_kprojid(struct user_namespace *to, kprojid_t kprojid)
+{
+ return __kprojid_val(kprojid);
+}
+
+static inline projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t kprojid)
+{
+ projid_t projid = from_kprojid(to, kprojid);
+ if (projid == (projid_t)-1)
+ projid = OVERFLOW_PROJID;
+ return projid;
+}
+
+static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
+{
+ return true;
+}
+
+#endif /* CONFIG_USER_NS */
+
+#endif /* _LINUX_PROJID_H */
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index 4e72922e5a751c150386e4eb9f8e961ac1051d67..95142cae446a7205e9887029a7433eff1b147d81 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -20,6 +20,7 @@ struct uid_gid_map { /* 64 bytes -- 1 cache line */
struct user_namespace {
struct uid_gid_map uid_map;
struct uid_gid_map gid_map;
+ struct uid_gid_map projid_map;
struct kref kref;
struct user_namespace *parent;
kuid_t owner;
@@ -49,8 +50,10 @@ static inline void put_user_ns(struct user_namespace *ns)
struct seq_operations;
extern struct seq_operations proc_uid_seq_operations;
extern struct seq_operations proc_gid_seq_operations;
+extern struct seq_operations proc_projid_seq_operations;
extern ssize_t proc_uid_map_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t proc_gid_map_write(struct file *, const char __user *, size_t, loff_t *);
+extern ssize_t proc_projid_map_write(struct file *, const char __user *, size_t, loff_t *);
#else
static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
diff --git a/kernel/user.c b/kernel/user.c
index b815fefbe76fa4743bd3081af6c6e469dff2f4db..750acffbe9ec5b20191607040c7ec8e840158253 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -38,6 +38,14 @@ struct user_namespace init_user_ns = {
.count = 4294967295U,
},
},
+ .projid_map = {
+ .nr_extents = 1,
+ .extent[0] = {
+ .first = 0,
+ .lower_first = 0,
+ .count = 4294967295U,
+ },
+ },
.kref = {
.refcount = ATOMIC_INIT(3),
},
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 86602316422d203fffb8c530cbf44f825199a5f7..456a6b9fba34f3104bc9db64119acd9d3fdfa8df 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -19,6 +19,7 @@
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
+#include <linux/projid.h>
static struct kmem_cache *user_ns_cachep __read_mostly;
@@ -295,6 +296,75 @@ gid_t from_kgid_munged(struct user_namespace *targ, kgid_t kgid)
}
EXPORT_SYMBOL(from_kgid_munged);
+/**
+ * make_kprojid - Map a user-namespace projid pair into a kprojid.
+ * @ns: User namespace that the projid is in
+ * @projid: Project identifier
+ *
+ * Maps a user-namespace uid pair into a kernel internal kuid,
+ * and returns that kuid.
+ *
+ * When there is no mapping defined for the user-namespace projid
+ * pair INVALID_PROJID is returned. Callers are expected to test
+ * for and handle handle INVALID_PROJID being returned. INVALID_PROJID
+ * may be tested for using projid_valid().
+ */
+kprojid_t make_kprojid(struct user_namespace *ns, projid_t projid)
+{
+ /* Map the uid to a global kernel uid */
+ return KPROJIDT_INIT(map_id_down(&ns->projid_map, projid));
+}
+EXPORT_SYMBOL(make_kprojid);
+
+/**
+ * from_kprojid - Create a projid from a kprojid user-namespace pair.
+ * @targ: The user namespace we want a projid in.
+ * @kprojid: The kernel internal project identifier to start with.
+ *
+ * Map @kprojid into the user-namespace specified by @targ and
+ * return the resulting projid.
+ *
+ * There is always a mapping into the initial user_namespace.
+ *
+ * If @kprojid has no mapping in @targ (projid_t)-1 is returned.
+ */
+projid_t from_kprojid(struct user_namespace *targ, kprojid_t kprojid)
+{
+ /* Map the uid from a global kernel uid */
+ return map_id_up(&targ->projid_map, __kprojid_val(kprojid));
+}
+EXPORT_SYMBOL(from_kprojid);
+
+/**
+ * from_kprojid_munged - Create a projiid from a kprojid user-namespace pair.
+ * @targ: The user namespace we want a projid in.
+ * @kprojid: The kernel internal projid to start with.
+ *
+ * Map @kprojid into the user-namespace specified by @targ and
+ * return the resulting projid.
+ *
+ * There is always a mapping into the initial user_namespace.
+ *
+ * Unlike from_kprojid from_kprojid_munged never fails and always
+ * returns a valid projid. This makes from_kprojid_munged
+ * appropriate for use in syscalls like stat and where
+ * failing the system call and failing to provide a valid projid are
+ * not an options.
+ *
+ * If @kprojid has no mapping in @targ OVERFLOW_PROJID is returned.
+ */
+projid_t from_kprojid_munged(struct user_namespace *targ, kprojid_t kprojid)
+{
+ projid_t projid;
+ projid = from_kprojid(targ, kprojid);
+
+ if (projid == (projid_t) -1)
+ projid = OVERFLOW_PROJID;
+ return projid;
+}
+EXPORT_SYMBOL(from_kprojid_munged);
+
+
static int uid_m_show(struct seq_file *seq, void *v)
{
struct user_namespace *ns = seq->private;
@@ -337,6 +407,27 @@ static int gid_m_show(struct seq_file *seq, void *v)
return 0;
}
+static int projid_m_show(struct seq_file *seq, void *v)
+{
+ struct user_namespace *ns = seq->private;
+ struct uid_gid_extent *extent = v;
+ struct user_namespace *lower_ns;
+ projid_t lower;
+
+ lower_ns = seq_user_ns(seq);
+ if ((lower_ns == ns) && lower_ns->parent)
+ lower_ns = lower_ns->parent;
+
+ lower = from_kprojid(lower_ns, KPROJIDT_INIT(extent->lower_first));
+
+ seq_printf(seq, "%10u %10u %10u\n",
+ extent->first,
+ lower,
+ extent->count);
+
+ return 0;
+}
+
static void *m_start(struct seq_file *seq, loff_t *ppos, struct uid_gid_map *map)
{
struct uid_gid_extent *extent = NULL;
@@ -362,6 +453,13 @@ static void *gid_m_start(struct seq_file *seq, loff_t *ppos)
return m_start(seq, ppos, &ns->gid_map);
}
+static void *projid_m_start(struct seq_file *seq, loff_t *ppos)
+{
+ struct user_namespace *ns = seq->private;
+
+ return m_start(seq, ppos, &ns->projid_map);
+}
+
static void *m_next(struct seq_file *seq, void *v, loff_t *pos)
{
(*pos)++;
@@ -387,6 +485,13 @@ struct seq_operations proc_gid_seq_operations = {
.show = gid_m_show,
};
+struct seq_operations proc_projid_seq_operations = {
+ .start = projid_m_start,
+ .stop = m_stop,
+ .next = m_next,
+ .show = projid_m_show,
+};
+
static DEFINE_MUTEX(id_map_mutex);
static ssize_t map_write(struct file *file, const char __user *buf,
@@ -434,7 +539,7 @@ static ssize_t map_write(struct file *file, const char __user *buf,
/* Require the appropriate privilege CAP_SETUID or CAP_SETGID
* over the user namespace in order to set the id mapping.
*/
- if (!ns_capable(ns, cap_setid))
+ if (cap_valid(cap_setid) && !ns_capable(ns, cap_setid))
goto out;
/* Get a buffer */
@@ -584,9 +689,30 @@ ssize_t proc_gid_map_write(struct file *file, const char __user *buf, size_t siz
&ns->gid_map, &ns->parent->gid_map);
}
+ssize_t proc_projid_map_write(struct file *file, const char __user *buf, size_t size, loff_t *ppos)
+{
+ struct seq_file *seq = file->private_data;
+ struct user_namespace *ns = seq->private;
+ struct user_namespace *seq_ns = seq_user_ns(seq);
+
+ if (!ns->parent)
+ return -EPERM;
+
+ if ((seq_ns != ns) && (seq_ns != ns->parent))
+ return -EPERM;
+
+ /* Anyone can set any valid project id no capability needed */
+ return map_write(file, buf, size, ppos, -1,
+ &ns->projid_map, &ns->parent->projid_map);
+}
+
static bool new_idmap_permitted(struct user_namespace *ns, int cap_setid,
struct uid_gid_map *new_map)
{
+ /* Allow anyone to set a mapping that doesn't require privilege */
+ if (!cap_valid(cap_setid))
+ return true;
+
/* Allow the specified ids if we have the appropriate capability
* (CAP_SETUID or CAP_SETGID) over the parent user namespace.
*/