ath6kl: add tracing points for sdio transfers

[cascardo/linux.git] / fs / namespace.c

diff --git a/fs/namespace.c b/fs/namespace.c
index 4dfcaf0..55605c5 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -313,7 +313,7 @@ int __mnt_want_write(struct vfsmount *m)
         * incremented count after it has set MNT_WRITE_HOLD.
         */
        smp_mb();
-       while (mnt->mnt.mnt_flags & MNT_WRITE_HOLD)
+       while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
                cpu_relax();
        /*
         * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
@@ -1269,7 +1269,7 @@ SYSCALL_DEFINE2(umount, char __user *, name, int, flags)
                goto dput_and_out;
 
        retval = -EPERM;
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(mnt->mnt_ns->user_ns, CAP_SYS_ADMIN))
                goto dput_and_out;
 
        retval = do_umount(mnt, flags);
@@ -1295,7 +1295,7 @@ SYSCALL_DEFINE1(oldumount, char __user *, name)
 
 static int mount_is_safe(struct path *path)
 {
-       if (capable(CAP_SYS_ADMIN))
+       if (ns_capable(real_mount(path->mnt)->mnt_ns->user_ns, CAP_SYS_ADMIN))
                return 0;
        return -EPERM;
 #ifdef notyet
@@ -1633,7 +1633,7 @@ static int do_change_type(struct path *path, int flag)
        int type;
        int err = 0;
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(mnt->mnt_ns->user_ns, CAP_SYS_ADMIN))
                return -EPERM;
 
        if (path->dentry != path->mnt->mnt_root)
@@ -1797,7 +1797,7 @@ static int do_move_mount(struct path *path, const char *old_name)
        struct mount *p;
        struct mount *old;
        int err = 0;
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(real_mount(path->mnt)->mnt_ns->user_ns, CAP_SYS_ADMIN))
                return -EPERM;
        if (!old_name || !*old_name)
                return -EINVAL;
@@ -1884,21 +1884,6 @@ static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
        return ERR_PTR(err);
 }
 
-static struct vfsmount *
-do_kern_mount(const char *fstype, int flags, const char *name, void *data)
-{
-       struct file_system_type *type = get_fs_type(fstype);
-       struct vfsmount *mnt;
-       if (!type)
-               return ERR_PTR(-ENODEV);
-       mnt = vfs_kern_mount(type, flags, name, data);
-       if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
-           !mnt->mnt_sb->s_subtype)
-               mnt = fs_set_subtype(mnt, fstype);
-       put_filesystem(type);
-       return mnt;
-}
-
 /*
  * add a mount into a namespace's mount tree
  */
@@ -1944,20 +1929,46 @@ unlock:
  * create a new mount for userspace and request it to be added into the
  * namespace's tree
  */
-static int do_new_mount(struct path *path, const char *type, int flags,
+static int do_new_mount(struct path *path, const char *fstype, int flags,
                        int mnt_flags, const char *name, void *data)
 {
+       struct file_system_type *type;
+       struct user_namespace *user_ns;
        struct vfsmount *mnt;
        int err;
 
-       if (!type)
+       if (!fstype)
                return -EINVAL;
 
        /* we need capabilities... */
-       if (!capable(CAP_SYS_ADMIN))
+       user_ns = real_mount(path->mnt)->mnt_ns->user_ns;
+       if (!ns_capable(user_ns, CAP_SYS_ADMIN))
                return -EPERM;
 
-       mnt = do_kern_mount(type, flags, name, data);
+       type = get_fs_type(fstype);
+       if (!type)
+               return -ENODEV;
+
+       if (user_ns != &init_user_ns) {
+               if (!(type->fs_flags & FS_USERNS_MOUNT)) {
+                       put_filesystem(type);
+                       return -EPERM;
+               }
+               /* Only in special cases allow devices from mounts
+                * created outside the initial user namespace.
+                */
+               if (!(type->fs_flags & FS_USERNS_DEV_MOUNT)) {
+                       flags |= MS_NODEV;
+                       mnt_flags |= MNT_NODEV;
+               }
+       }
+
+       mnt = vfs_kern_mount(type, flags, name, data);
+       if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
+           !mnt->mnt_sb->s_subtype)
+               mnt = fs_set_subtype(mnt, fstype);
+
+       put_filesystem(type);
        if (IS_ERR(mnt))
                return PTR_ERR(mnt);
 
@@ -2290,6 +2301,7 @@ dput_out:
 
 static void free_mnt_ns(struct mnt_namespace *ns)
 {
+       proc_free_inum(ns->proc_inum);
        put_user_ns(ns->user_ns);
        kfree(ns);
 }
@@ -2306,10 +2318,16 @@ static atomic64_t mnt_ns_seq = ATOMIC64_INIT(1);
 static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns)
 {
        struct mnt_namespace *new_ns;
+       int ret;
 
        new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
        if (!new_ns)
                return ERR_PTR(-ENOMEM);
+       ret = proc_alloc_inum(&new_ns->proc_inum);
+       if (ret) {
+               kfree(new_ns);
+               return ERR_PTR(ret);
+       }
        new_ns->seq = atomic64_add_return(1, &mnt_ns_seq);
        atomic_set(&new_ns->count, 1);
        new_ns->root = NULL;
@@ -2549,7 +2567,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
        struct mount *new_mnt, *root_mnt;
        int error;
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN))
                return -EPERM;
 
        error = user_path_dir(new_root, &new);
@@ -2631,8 +2649,13 @@ static void __init init_mount_tree(void)
        struct vfsmount *mnt;
        struct mnt_namespace *ns;
        struct path root;
+       struct file_system_type *type;
 
-       mnt = do_kern_mount("rootfs", 0, "rootfs", NULL);
+       type = get_fs_type("rootfs");
+       if (!type)
+               panic("Can't find rootfs type");
+       mnt = vfs_kern_mount(type, 0, "rootfs", NULL);
+       put_filesystem(type);
        if (IS_ERR(mnt))
                panic("Can't create rootfs");
 
@@ -2757,8 +2780,10 @@ static int mntns_install(struct nsproxy *nsproxy, void *ns)
        struct mnt_namespace *mnt_ns = ns;
        struct path root;
 
-       if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_CHROOT))
-               return -EINVAL;
+       if (!ns_capable(mnt_ns->user_ns, CAP_SYS_ADMIN) ||
+           !nsown_capable(CAP_SYS_CHROOT) ||
+           !nsown_capable(CAP_SYS_ADMIN))
+               return -EPERM;
 
        if (fs->users != 1)
                return -EINVAL;
@@ -2782,10 +2807,17 @@ static int mntns_install(struct nsproxy *nsproxy, void *ns)
        return 0;
 }
 
+static unsigned int mntns_inum(void *ns)
+{
+       struct mnt_namespace *mnt_ns = ns;
+       return mnt_ns->proc_inum;
+}
+
 const struct proc_ns_operations mntns_operations = {
        .name           = "mnt",
        .type           = CLONE_NEWNS,
        .get            = mntns_get,
        .put            = mntns_put,
        .install        = mntns_install,
+       .inum           = mntns_inum,
 };