Subject: Re: [PATCH] xfrm: use printk instead of WARN for bad policy reporting

From: Vegard Nossum <[email-masked]>
Date: Wed, 20 Jul 2016 13:53:12 +0200

On 07/20/2016 10:32 AM, Vegard Nossum wrote:
> AFAICT this message is just printed whenever input validation fails.
> This is a normal failure and we shouldn't be dumping the stack over it.
>
> Looks like it was originally a printk that was maybe incorrectly
> upgraded to a WARN:
>
> commit 62db5cfd70b1ef53aa21f144a806fe3b78c84fab
> Author: stephen hemminger <[email-masked]>
> Date:   Wed May 12 06:37:06 2010 +0000
>
>      xfrm: add severity to printk

Just FYI I'm also running into the

// reset the timers here?
WARN(1, "Don't know what to do with soft policy expire\n");

in xfrm_add_pol_expire() from the same commit, but that looks
potentially somewhat more serious (or at least it looks like we might
want to do some sort of cleaning up), so I won't touch it for now.

Added some more XFRM people to Cc.

Vegard

 > Cc: Stephen Hemminger <[email-masked]>
 > Signed-off-by: Vegard Nossum <[email-masked]>
 > ---
 >   net/xfrm/xfrm_user.c | 2 +-
 >   1 file changed, 1 insertion(+), 1 deletion(-)
 >
 > diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
 > index 4fb04ce..0b81bfc 100644
 > --- a/net/xfrm/xfrm_user.c
 > +++ b/net/xfrm/xfrm_user.c
 > @@ -2150,7 +2150,7 @@ static int xfrm_add_acquire(struct sk_buff 
*skb, struct nlmsghdr *nlh,
 >   	return 0;
 >
 >   bad_policy:
 > -	WARN(1, "BAD policy passed\n");
 > +	printk(KERN_WARNING "xfrm_user: bad policy passed\n");
 >   free_state:
 >   	kfree(x);
 >   nomem:
 >