#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;
}
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;
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;
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)++;
.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,
/* 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 */
&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.
*/
projects / cascardo / linux.git / blobdiff