Merge tag 'omap-for-v3.10/timer-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/drivers

From Tony Lindgren <tony@atomide.com>:

Clean-up for omap2+ timers from Jon Hunter <jon-hunter@ti.com>:

This series consists mainly of clean-ups for clockevents and
clocksource timers on OMAP2+ devices. The most significant change
in functionality comes from the 5th patch which is changing the
selection of the clocksource timer for OMAP3 and AM335x devices
when gptimers are used for clocksource.

Note that this series depends on 7185684 (ARM: OMAP: use
consistent error checking) in RMK's tree and 960cba6 (ARM:
OMAP5: timer: Update the clocksource name as per clock data)
in omap-for-v3.10/fixes-non-critical. So this branch is based
on a merge of 7185684 and omap-for-v3.10/fixes-non-critical
to avoid non-trivial merge conflicts.

* tag 'omap-for-v3.10/timer-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP4+: Fix sparse warning in system timers
  ARM: OMAP2+: Store ID of system timers in timer structure
  ARM: OMAP3: Update clocksource timer selection
  ARM: OMAP2+: Simplify system timers definitions
  ARM: OMAP2+: Simplify system timer clock definitions
  ARM: OMAP2+: Remove hard-coded test on timer ID
  ARM: OMAP2+: Display correct system timer name
  ARM: OMAP2+: fix typo "CONFIG_BRIDGE_DVFS"
  ARM: OMAP1: remove "config MACH_OMAP_HTCWIZARD"
  ARM: OMAP: dpll: enable bypass clock only when attempting dpll bypass
  ARM: OMAP2+: powerdomain: avoid testing whether an unsigned char is less than 0
  ARM: OMAP2+: hwmod: Remove unused _HWMOD_WAKEUP_ENABLED flag
  ARM: OMAP2+: am335x: Change the wdt1 func clk src to per_32k clk
  ARM: OMAP2+: AM33xx: hwmod: Add missing sysc definition to wdt1 entry

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 53 insertions, 1 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 50ca17d3cb45..d581e45c0a9f 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -798,6 +798,10 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
         }
 
         mnt->mnt.mnt_flags = old->mnt.mnt_flags & ~MNT_WRITE_HOLD;
+        /* Don't allow unprivileged users to change mount flags */
+        if ((flag & CL_UNPRIVILEGED) && (mnt->mnt.mnt_flags & MNT_READONLY))
+                mnt->mnt.mnt_flags |= MNT_LOCK_READONLY;
+
         atomic_inc(&sb->s_active);
         mnt->mnt.mnt_sb = sb;
         mnt->mnt.mnt_root = dget(root);
@@ -1713,6 +1717,9 @@ static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
         if (readonly_request == __mnt_is_readonly(mnt))
                 return 0;
 
+        if (mnt->mnt_flags & MNT_LOCK_READONLY)
+                return -EPERM;
+
         if (readonly_request)
                 error = mnt_make_readonly(real_mount(mnt));
         else
@@ -2339,7 +2346,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
         /* First pass: copy the tree topology */
         copy_flags = CL_COPY_ALL | CL_EXPIRE;
         if (user_ns != mnt_ns->user_ns)
-                copy_flags |= CL_SHARED_TO_SLAVE;
+                copy_flags |= CL_SHARED_TO_SLAVE | CL_UNPRIVILEGED;
         new = copy_tree(old, old->mnt.mnt_root, copy_flags);
         if (IS_ERR(new)) {
                 up_write(&namespace_sem);
@@ -2732,6 +2739,51 @@ bool our_mnt(struct vfsmount *mnt)
         return check_mnt(real_mount(mnt));
 }
 
+bool current_chrooted(void)
+{
+        /* Does the current process have a non-standard root */
+        struct path ns_root;
+        struct path fs_root;
+        bool chrooted;
+
+        /* Find the namespace root */
+        ns_root.mnt = &current->nsproxy->mnt_ns->root->mnt;
+        ns_root.dentry = ns_root.mnt->mnt_root;
+        path_get(&ns_root);
+        while (d_mountpoint(ns_root.dentry) && follow_down_one(&ns_root))
+                ;
+
+        get_fs_root(current->fs, &fs_root);
+
+        chrooted = !path_equal(&fs_root, &ns_root);
+
+        path_put(&fs_root);
+        path_put(&ns_root);
+
+        return chrooted;
+}
+
+void update_mnt_policy(struct user_namespace *userns)
+{
+        struct mnt_namespace *ns = current->nsproxy->mnt_ns;
+        struct mount *mnt;
+
+        down_read(&namespace_sem);
+        list_for_each_entry(mnt, &ns->list, mnt_list) {
+                switch (mnt->mnt.mnt_sb->s_magic) {
+                case SYSFS_MAGIC:
+                        userns->may_mount_sysfs = true;
+                        break;
+                case PROC_SUPER_MAGIC:
+                        userns->may_mount_proc = true;
+                        break;
+                }
+                if (userns->may_mount_sysfs && userns->may_mount_proc)
+                        break;
+        }
+        up_read(&namespace_sem);
+}
+
 static void *mntns_get(struct task_struct *task)
 {
         struct mnt_namespace *ns = NULL;