perf report: Drop cycles 0 for LBR print

[mirror_ubuntu-artful-kernel.git] / fs / super.c

diff --git a/fs/super.c b/fs/super.c
index ea662b0e5e789f63b018ba6d59f5d946ba0c74ef..b8b6a086c03b9a5478dc6a67e0b5054127032f47 100644 (file)
--- a/fs/super.c
+++ b/fs/super.c
@@ -469,7 +469,7 @@ struct super_block *sget_userns(struct file_system_type *type,
        struct super_block *old;
        int err;
 
-       if (!(flags & MS_KERNMOUNT) &&
+       if (!(flags & (MS_KERNMOUNT|MS_SUBMOUNT)) &&
            !(type->fs_flags & FS_USERNS_MOUNT) &&
            !capable(CAP_SYS_ADMIN))
                return ERR_PTR(-EPERM);
@@ -499,7 +499,7 @@ retry:
        }
        if (!s) {
                spin_unlock(&sb_lock);
-               s = alloc_super(type, flags, user_ns);
+               s = alloc_super(type, (flags & ~MS_SUBMOUNT), user_ns);
                if (!s)
                        return ERR_PTR(-ENOMEM);
                goto retry;
@@ -540,8 +540,15 @@ struct super_block *sget(struct file_system_type *type,
 {
        struct user_namespace *user_ns = current_user_ns();
 
+       /* We don't yet pass the user namespace of the parent
+        * mount through to here so always use &init_user_ns
+        * until that changes.
+        */
+       if (flags & MS_SUBMOUNT)
+               user_ns = &init_user_ns;
+
        /* Ensure the requestor has permissions over the target filesystem */
-       if (!(flags & MS_KERNMOUNT) && !ns_capable(user_ns, CAP_SYS_ADMIN))
+       if (!(flags & (MS_KERNMOUNT|MS_SUBMOUNT)) && !ns_capable(user_ns, CAP_SYS_ADMIN))
                return ERR_PTR(-EPERM);
 
        return sget_userns(type, test, set, flags, user_ns, data);