5 files changed, 102 insertions, 16 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index f9bd395b3473..dc4c5a7b9ece 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -81,6 +81,7 @@
 #include <linux/pid_namespace.h>
 #include <linux/ptrace.h>
 #include <linux/tracehook.h>
+#include <linux/user_namespace.h>
 
 #include <asm/pgtable.h>
 #include <asm/processor.h>
@@ -161,6 +162,7 @@ static inline const char *get_task_state(struct task_struct *tsk)
 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
                                 struct pid *pid, struct task_struct *p)
 {
+        struct user_namespace *user_ns = current_user_ns();
         struct group_info *group_info;
         int g;
         struct fdtable *fdt = NULL;
@@ -189,8 +191,14 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
                 task_tgid_nr_ns(p, ns),
                 pid_nr_ns(pid, ns),
                 ppid, tpid,
-                cred->uid, cred->euid, cred->suid, cred->fsuid,
-                cred->gid, cred->egid, cred->sgid, cred->fsgid);
+                from_kuid_munged(user_ns, cred->uid),
+                from_kuid_munged(user_ns, cred->euid),
+                from_kuid_munged(user_ns, cred->suid),
+                from_kuid_munged(user_ns, cred->fsuid),
+                from_kgid_munged(user_ns, cred->gid),
+                from_kgid_munged(user_ns, cred->egid),
+                from_kgid_munged(user_ns, cred->sgid),
+                from_kgid_munged(user_ns, cred->fsgid));
 
         task_lock(p);
         if (p->files)
@@ -205,7 +213,8 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
         task_unlock(p);
 
         for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
-                seq_printf(m, "%d ", GROUP_AT(group_info, g));
+                seq_printf(m, "%d ",
+                           from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
         put_cred(cred);
 
         seq_putc(m, '\n');
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 57b8159f26f3..d2d3108a611c 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -81,6 +81,7 @@
 #include <linux/oom.h>
 #include <linux/elf.h>
 #include <linux/pid_namespace.h>
+#include <linux/user_namespace.h>
 #include <linux/fs_struct.h>
 #include <linux/slab.h>
 #include <linux/flex_array.h>
@@ -1561,8 +1562,8 @@ int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
         generic_fillattr(inode, stat);
 
         rcu_read_lock();
-        stat->uid = 0;
-        stat->gid = 0;
+        stat->uid = GLOBAL_ROOT_UID;
+        stat->gid = GLOBAL_ROOT_GID;
         task = pid_task(proc_pid(inode), PIDTYPE_PID);
         if (task) {
                 if (!has_pid_permissions(pid, task, 2)) {
@@ -1622,8 +1623,8 @@ int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
                         inode->i_gid = cred->egid;
                         rcu_read_unlock();
                 } else {
-                        inode->i_uid = 0;
-                        inode->i_gid = 0;
+                        inode->i_uid = GLOBAL_ROOT_UID;
+                        inode->i_gid = GLOBAL_ROOT_GID;
                 }
                 inode->i_mode &= ~(S_ISUID | S_ISGID);
                 security_task_to_inode(task, inode);
@@ -1815,8 +1816,8 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
                                         inode->i_gid = cred->egid;
                                         rcu_read_unlock();
                                 } else {
-                                        inode->i_uid = 0;
-                                        inode->i_gid = 0;
+                                        inode->i_uid = GLOBAL_ROOT_UID;
+                                        inode->i_gid = GLOBAL_ROOT_GID;
                                 }
 
                                 i_mode = S_IFLNK;
@@ -2045,8 +2046,8 @@ static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
                         inode->i_gid = cred->egid;
                         rcu_read_unlock();
                 } else {
-                        inode->i_uid = 0;
-                        inode->i_gid = 0;
+                        inode->i_uid = GLOBAL_ROOT_UID;
+                        inode->i_gid = GLOBAL_ROOT_GID;
                 }
                 security_task_to_inode(task, inode);
                 status = 1;
@@ -2924,6 +2925,74 @@ static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
 }
 #endif /* CONFIG_TASK_IO_ACCOUNTING */
 
+#ifdef CONFIG_USER_NS
+static int proc_id_map_open(struct inode *inode, struct file *file,
+        struct seq_operations *seq_ops)
+{
+        struct user_namespace *ns = NULL;
+        struct task_struct *task;
+        struct seq_file *seq;
+        int ret = -EINVAL;
+
+        task = get_proc_task(inode);
+        if (task) {
+                rcu_read_lock();
+                ns = get_user_ns(task_cred_xxx(task, user_ns));
+                rcu_read_unlock();
+                put_task_struct(task);
+        }
+        if (!ns)
+                goto err;
+
+        ret = seq_open(file, seq_ops);
+        if (ret)
+                goto err_put_ns;
+
+        seq = file->private_data;
+        seq->private = ns;
+
+        return 0;
+err_put_ns:
+        put_user_ns(ns);
+err:
+        return ret;
+}
+
+static int proc_id_map_release(struct inode *inode, struct file *file)
+{
+        struct seq_file *seq = file->private_data;
+        struct user_namespace *ns = seq->private;
+        put_user_ns(ns);
+        return seq_release(inode, file);
+}
+
+static int proc_uid_map_open(struct inode *inode, struct file *file)
+{
+        return proc_id_map_open(inode, file, &proc_uid_seq_operations);
+}
+
+static int proc_gid_map_open(struct inode *inode, struct file *file)
+{
+        return proc_id_map_open(inode, file, &proc_gid_seq_operations);
+}
+
+static const struct file_operations proc_uid_map_operations = {
+        .open           = proc_uid_map_open,
+        .write          = proc_uid_map_write,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = proc_id_map_release,
+};
+
+static const struct file_operations proc_gid_map_operations = {
+        .open           = proc_gid_map_open,
+        .write          = proc_gid_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,
                                 struct pid *pid, struct task_struct *task)
 {
@@ -3026,6 +3095,10 @@ static const struct pid_entry tgid_base_stuff[] = {
 #ifdef CONFIG_HARDWALL
         INF("hardwall",   S_IRUGO, proc_pid_hardwall),
 #endif
+#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),
+#endif
 };
 
 static int proc_tgid_base_readdir(struct file * filp,
@@ -3381,6 +3454,10 @@ static const struct pid_entry tid_base_stuff[] = {
 #ifdef CONFIG_HARDWALL
         INF("hardwall",   S_IRUGO, proc_pid_hardwall),
 #endif
+#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),
+#endif
 };
 
 static int proc_tid_base_readdir(struct file * filp,
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 205c92280838..554ecc54799f 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -108,8 +108,8 @@ static int proc_show_options(struct seq_file *seq, struct dentry *root)
         struct super_block *sb = root->d_sb;
         struct pid_namespace *pid = sb->s_fs_info;
 
-        if (pid->pid_gid)
-                seq_printf(seq, ",gid=%lu", (unsigned long)pid->pid_gid);
+        if (!gid_eq(pid->pid_gid, GLOBAL_ROOT_GID))
+                seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, pid->pid_gid));
         if (pid->hide_pid != 0)
                 seq_printf(seq, ",hidepid=%u", pid->hide_pid);
 
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 21d836f40292..3476bca8f7af 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -371,9 +371,9 @@ void register_sysctl_root(struct ctl_table_root *root)
 
 static int test_perm(int mode, int op)
 {
-        if (!current_euid())
+        if (uid_eq(current_euid(), GLOBAL_ROOT_UID))
                 mode >>= 6;
-        else if (in_egroup_p(0))
+        else if (in_egroup_p(GLOBAL_ROOT_GID))
                 mode >>= 3;
         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
                 return 0;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index eed44bfc85db..7c30fce037c0 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -67,7 +67,7 @@ static int proc_parse_options(char *options, struct pid_namespace *pid)
                 case Opt_gid:
                         if (match_int(&args[0], &option))
                                 return 0;
-                        pid->pid_gid = option;
+                        pid->pid_gid = make_kgid(current_user_ns(), option);
                         break;
                 case Opt_hidepid:
                         if (match_int(&args[0], &option))