From 667b60946ef9b8375085c7b225229923c6f87308 Mon Sep 17 00:00:00 2001 From: Marcos Paulo de Souza Date: Tue, 6 Feb 2018 15:39:34 -0800 Subject: kernel/fork.c: add comment about usage of CLONE_FS flags and namespaces All other places that deals with namespaces have an explanation of why the restriction is there. The description added in this commit was based on commit e66eded8309e ("userns: Don't allow CLONE_NEWUSER | CLONE_FS"). Link: http://lkml.kernel.org/r/20171112151637.13258-1-marcos.souza.org@gmail.com Signed-off-by: Marcos Paulo de Souza Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/fork.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index 0d62524c6660..b9d857fe2a5c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1587,6 +1587,10 @@ static __latent_entropy struct task_struct *copy_process( int retval; struct task_struct *p; + /* + * Don't allow sharing the root directory with processes in a different + * namespace + */ if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS)) return ERR_PTR(-EINVAL); -- cgit v1.2.3-59-g8ed1b