4 files changed, 97 insertions, 33 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index f7ed9ee46eb9..cbd0f1b324b9 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -143,6 +143,7 @@ static const char * const task_state_array[] = {
         "x (dead)",             /*  64 */
         "K (wakekill)",         /* 128 */
         "W (waking)",           /* 256 */
+        "P (parked)",           /* 512 */
 };
 
 static inline const char *get_task_state(struct task_struct *tsk)
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 4b3b3ffb52f1..21e1a8f1659d 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -755,37 +755,8 @@ void pde_put(struct proc_dir_entry *pde)
                 free_proc_entry(pde);
 }
 
-/*
- * Remove a /proc entry and free it if it's not currently in use.
- */
-void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+static void entry_rundown(struct proc_dir_entry *de)
 {
-        struct proc_dir_entry **p;
-        struct proc_dir_entry *de = NULL;
-        const char *fn = name;
-        unsigned int len;
-
-        spin_lock(&proc_subdir_lock);
-        if (__xlate_proc_name(name, &parent, &fn) != 0) {
-                spin_unlock(&proc_subdir_lock);
-                return;
-        }
-        len = strlen(fn);
-
-        for (p = &parent->subdir; *p; p=&(*p)->next ) {
-                if (proc_match(len, fn, *p)) {
-                        de = *p;
-                        *p = de->next;
-                        de->next = NULL;
-                        break;
-                }
-        }
-        spin_unlock(&proc_subdir_lock);
-        if (!de) {
-                WARN(1, "name '%s'\n", name);
-                return;
-        }
-
         spin_lock(&de->pde_unload_lock);
         /*
          * Stop accepting new callers into module. If you're
@@ -817,6 +788,40 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
                 spin_lock(&de->pde_unload_lock);
         }
         spin_unlock(&de->pde_unload_lock);
+}
+
+/*
+ * Remove a /proc entry and free it if it's not currently in use.
+ */
+void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+{
+        struct proc_dir_entry **p;
+        struct proc_dir_entry *de = NULL;
+        const char *fn = name;
+        unsigned int len;
+
+        spin_lock(&proc_subdir_lock);
+        if (__xlate_proc_name(name, &parent, &fn) != 0) {
+                spin_unlock(&proc_subdir_lock);
+                return;
+        }
+        len = strlen(fn);
+
+        for (p = &parent->subdir; *p; p=&(*p)->next ) {
+                if (proc_match(len, fn, *p)) {
+                        de = *p;
+                        *p = de->next;
+                        de->next = NULL;
+                        break;
+                }
+        }
+        spin_unlock(&proc_subdir_lock);
+        if (!de) {
+                WARN(1, "name '%s'\n", name);
+                return;
+        }
+
+        entry_rundown(de);
 
         if (S_ISDIR(de->mode))
                 parent->nlink--;
@@ -827,3 +832,57 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
         pde_put(de);
 }
 EXPORT_SYMBOL(remove_proc_entry);
+
+int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
+{
+        struct proc_dir_entry **p;
+        struct proc_dir_entry *root = NULL, *de, *next;
+        const char *fn = name;
+        unsigned int len;
+
+        spin_lock(&proc_subdir_lock);
+        if (__xlate_proc_name(name, &parent, &fn) != 0) {
+                spin_unlock(&proc_subdir_lock);
+                return -ENOENT;
+        }
+        len = strlen(fn);
+
+        for (p = &parent->subdir; *p; p=&(*p)->next ) {
+                if (proc_match(len, fn, *p)) {
+                        root = *p;
+                        *p = root->next;
+                        root->next = NULL;
+                        break;
+                }
+        }
+        if (!root) {
+                spin_unlock(&proc_subdir_lock);
+                return -ENOENT;
+        }
+        de = root;
+        while (1) {
+                next = de->subdir;
+                if (next) {
+                        de->subdir = next->next;
+                        next->next = NULL;
+                        de = next;
+                        continue;
+                }
+                spin_unlock(&proc_subdir_lock);
+
+                entry_rundown(de);
+                next = de->parent;
+                if (S_ISDIR(de->mode))
+                        next->nlink--;
+                de->nlink = 0;
+                if (de == root)
+                        break;
+                pde_put(de);
+
+                spin_lock(&proc_subdir_lock);
+                de = next;
+        }
+        pde_put(root);
+        return 0;
+}
+EXPORT_SYMBOL(remove_proc_subtree);
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index a86aebc9ba7c..869116c2afbe 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -446,9 +446,10 @@ static const struct file_operations proc_reg_file_ops_no_compat = {
 
 struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
 {
-        struct inode *inode = iget_locked(sb, de->low_ino);
+        struct inode *inode = new_inode_pseudo(sb);
 
-        if (inode && (inode->i_state & I_NEW)) {
+        if (inode) {
+                inode->i_ino = de->low_ino;
                 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
                 PROC_I(inode)->pde = de;
 
@@ -476,7 +477,6 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
                                 inode->i_fop = de->proc_fops;
                         }
                 }
-                unlock_new_inode(inode);
         } else
                pde_put(de);
         return inode;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index c6e9fac26bac..9c7fab1d23f0 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -16,6 +16,7 @@
 #include <linux/sched.h>
 #include <linux/module.h>
 #include <linux/bitops.h>
+#include <linux/user_namespace.h>
 #include <linux/mount.h>
 #include <linux/pid_namespace.h>
 #include <linux/parser.h>
@@ -108,6 +109,9 @@ static struct dentry *proc_mount(struct file_system_type *fs_type,
         } else {
                 ns = task_active_pid_ns(current);
                 options = data;
+
+                if (!current_user_ns()->may_mount_proc)
+                        return ERR_PTR(-EPERM);
         }
 
         sb = sget(fs_type, proc_test_super, proc_set_super, flags, ns);