lkml.org 
[lkml]   [2022]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 1/1] ns: Move MAX_PID_NS_LEVEL to ns_common.h, reuse it
Petr Vorel <pvorel@suse.cz> writes:

> Move MAX_PID_NS_LEVEL to ns_common.h and reuse it in check in
> user_namespace.c.

What is the motivation for this change?

Is it just that there is a bare number in create_user_ns and that is a
little ugly? Or is there something more motivating this?

Eric

>
> Signed-off-by: Petr Vorel <pvorel@suse.cz>
> ---
> Hi Christian, all,
>
> I don't see putting MAX_PID_NS_LEVEL into ns_common.h as an elegant
> solution but IMHO better than use a hardwired number or redefinition in
> user_namespace.h.
>
> Kind regards,
> Petr
>
> include/linux/ns_common.h | 3 +++
> include/linux/pid_namespace.h | 3 ---
> kernel/user_namespace.c | 2 +-
> 3 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/ns_common.h b/include/linux/ns_common.h
> index 0f1d024bd958..173fab9dadf7 100644
> --- a/include/linux/ns_common.h
> +++ b/include/linux/ns_common.h
> @@ -4,6 +4,9 @@
>
> #include <linux/refcount.h>
>
> +/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
> +#define MAX_PID_NS_LEVEL 32
> +
> struct proc_ns_operations;
>
> struct ns_common {
> diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
> index 07481bb87d4e..f814068012d0 100644
> --- a/include/linux/pid_namespace.h
> +++ b/include/linux/pid_namespace.h
> @@ -11,9 +11,6 @@
> #include <linux/ns_common.h>
> #include <linux/idr.h>
>
> -/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
> -#define MAX_PID_NS_LEVEL 32
> -
> struct fs_pin;
>
> struct pid_namespace {
> diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
> index 5481ba44a8d6..6ea6e263403d 100644
> --- a/kernel/user_namespace.c
> +++ b/kernel/user_namespace.c
> @@ -87,7 +87,7 @@ int create_user_ns(struct cred *new)
> int ret, i;
>
> ret = -ENOSPC;
> - if (parent_ns->level > 32)
> + if (parent_ns->level > MAX_PID_NS_LEVEL)
> goto fail;
>
> ucounts = inc_user_namespaces(parent_ns, owner);

\
 
 \ /
  Last update: 2022-03-25 14:31    [W:0.065 / U:0.572 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site