From 137fdcc18a5979b53c0a1379b25fc68724e98a45 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Wed, 11 Sep 2013 14:26:06 -0700 Subject: initmpfs: replace MS_NOUSER in initramfs Mounting MS_NOUSER prevents --bind mounts from rootfs. Prevent new rootfs mounts with a different mechanism that doesn't affect bind mounts. Signed-off-by: Rob Landley Cc: Jeff Layton Cc: Jens Axboe Cc: Stephen Warren Cc: Rusty Russell Cc: Jim Cromie Cc: Sam Ravnborg Cc: Greg Kroah-Hartman Cc: "Eric W. Biederman" Cc: Alexander Viro Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ramfs/inode.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'fs/ramfs') diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c index c24f1e10b946..8f7fe323e049 100644 --- a/fs/ramfs/inode.c +++ b/fs/ramfs/inode.c @@ -247,7 +247,12 @@ struct dentry *ramfs_mount(struct file_system_type *fs_type, static struct dentry *rootfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { - return mount_nodev(fs_type, flags|MS_NOUSER, data, ramfs_fill_super); + static unsigned long once; + + if (test_and_set_bit(1, &once)) + return ERR_PTR(-ENODEV); + + return mount_nodev(fs_type, flags, data, ramfs_fill_super); } static void ramfs_kill_sb(struct super_block *sb) -- cgit v1.2.3-55-g7522