From: Miklos Szeredi I'm resending this patch, because I still believe it's the correct fix. Tested before/after applying the patch with a test application available from: http://www.inf.bme.hu/~mszeredi/nstest.c Bind mount from a foreign namespace results in an un-removable mount. The reason is that mnt->mnt_namespace is copied from the old mount in clone_mnt(). Because of this check_mnt() in sys_umount() will fail. The solution is to set mnt->mnt_namespace to current->namespace in clone_mnt(). clone_mnt() is either called from do_loopback() or copy_tree(). copy_tree() is called from do_loopback() or copy_namespace(). When called (directly or indirectly) from do_loopback(), always current->namspace is being modified: check_mnt(nd->mnt). So setting mnt->mnt_namespace to current->namspace is the right thing to do. When called from copy_namespace(), the setting of mnt_namespace is irrelevant, since mnt_namespace is reset later in that function for all copied mounts. Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton --- fs/namespace.c | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN fs/namespace.c~namespacec-fix-bind-mount-from-foreign-namespace fs/namespace.c --- 25/fs/namespace.c~namespacec-fix-bind-mount-from-foreign-namespace Mon May 16 14:56:25 2005 +++ 25-akpm/fs/namespace.c Mon May 16 14:56:25 2005 @@ -160,7 +160,7 @@ clone_mnt(struct vfsmount *old, struct d mnt->mnt_root = dget(root); mnt->mnt_mountpoint = mnt->mnt_root; mnt->mnt_parent = mnt; - mnt->mnt_namespace = old->mnt_namespace; + mnt->mnt_namespace = current->namespace; /* stick the duplicate mount on the same expiry list * as the original if that was on one */ _