Subject: Re: [PATCH net] inet_diag: fix inet_diag_msg_attrs_fill() for net_cls cgroup

From: Leon Romanovsky <[email-masked]>
Date: Tue, 9 May 2023 10:48:29 +0300

On Mon, May 08, 2023 at 09:21:26AM -0700, Kuniyuki Iwashima wrote:
> From: Leon Romanovsky <[email-masked]>
> Date: Mon, 8 May 2023 09:17:49 +0300
> > On Mon, May 08, 2023 at 05:32:33AM +0200, Patryk Sondej wrote:
> > > This commit fixes inet_diag_msg_attrs_fill() function in the ipv4/inet_diag.c file.
> > > The problem was that the function was using CONFIG_SOCK_CGROUP_DATA to check for the net_cls cgroup.
> > > However, the net_cls cgroup is defined by CONFIG_CGROUP_NET_CLASSID instead.
> > > 
> > > Therefore, this commit updates the #ifdef statement to CONFIG_CGROUP_NET_CLASSID,
> > > and uses the sock_cgroup_classid() function to retrieve the classid from the socket cgroup.
> > > 
> > > This change ensures that the function correctly retrieves the classid for the net_cls cgroup
> > > and fixes any issues related to the use of the function in this context.
> > > 
> > 
> > Please add Fixes line here.
> > 
> > > Signed-off-by: Patryk Sondej <[email-masked]>
> > > ---
> > >  net/ipv4/inet_diag.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
> > > index b812eb36f0e3..7017f88911a6 100644
> > > --- a/net/ipv4/inet_diag.c
> > > +++ b/net/ipv4/inet_diag.c
> > > @@ -157,7 +157,7 @@ int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
> > >  	    ext & (1 << (INET_DIAG_TCLASS - 1))) {
> > >  		u32 classid = 0;
> > >  
> > > -#ifdef CONFIG_SOCK_CGROUP_DATA
> > > +#ifdef CONFIG_CGROUP_NET_CLASSID
> > 
> > This ifdef should be deleted as sock_cgroup_classid() already has right ifdef.
> 
> sock_cgroup_classid() is defined under #ifdef CONFIG_SOCK_CGROUP_DATA,

Not in my kernel tree, where do you see it?

https://elixir.bootlin.com/linux/v6.4-rc1/source/include/linux/cgroup-defs.h#L809
include/linux/cgroup-defs.h
  809 static inline u32 sock_cgroup_classid(const struct sock_cgroup_data *skcd)
  810 {
  811 #ifdef CONFIG_CGROUP_NET_CLASSID
  812         return READ_ONCE(skcd->classid);
  813 #else
  814         return 0;
  815 #endif
  816 }

Thanks