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

From: Vegard Nossum <[email-masked]>
Date: Wed, 27 Jul 2016 08:03:18 +0200

On 07/20/2016 02:15 PM, Steffen Klassert wrote:
> On Wed, Jul 20, 2016 at 10:32:35AM +0200, 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
>>
>> 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");
>
> Why should we print here anything at all? If it is a normal
> configuration error, we should remove the printing.
>

New patch attached. Thanks,

Vegard
>>From 5bc56901bfea60e8d521f859ce73180796df0e56 Mon Sep 17 00:00:00 2001
From: Vegard Nossum <[email-masked]>
Date: Tue, 19 Jul 2016 23:41:16 -0700
Subject: [PATCH] xfrm: get rid of incorrect WARN

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

Cc: Stephen Hemminger <[email-masked]>
Cc: Steffen Klassert <[email-masked]>
Signed-off-by: Vegard Nossum <[email-masked]>
---
 net/xfrm/xfrm_user.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index d516845..2477b24 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2117,7 +2117,7 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	err = verify_newpolicy_info(&ua->policy);
 	if (err)
-		goto bad_policy;
+		goto free_state;
 
 	/*   build an XP */
 	xp = xfrm_policy_construct(net, &ua->policy, attrs, &err);
@@ -2149,8 +2149,6 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	return 0;
 
-bad_policy:
-	WARN(1, "BAD policy passed\n");
 free_state:
 	kfree(x);
 nomem:
-- 
1.9.1