lkml.org 
[lkml]   [2020]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2] xfrm: policy: Fix xfrm policy match
From
Date
On 2020/5/21 14:49, Xin Long wrote:
> On Tue, May 19, 2020 at 4:53 PM Steffen Klassert
> <steffen.klassert@secunet.com> wrote:
>>
>> On Fri, May 15, 2020 at 04:39:57PM +0800, Yuehaibing wrote:
>>>
>>> Friendly ping...
>>>
>>> Any plan for this issue?
>>
>> There was still no consensus between you and Xin on how
>> to fix this issue. Once this happens, I consider applying
>> a fix.
>>
> Sorry, Yuehaibing, I can't really accept to do: (A->mark.m & A->mark.v)
> I'm thinking to change to:
>
> static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
> struct xfrm_policy *pol)
> {
> - u32 mark = policy->mark.v & policy->mark.m;
> -
> - if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
> - return true;
> -
> - if ((mark & pol->mark.m) == pol->mark.v &&
> - policy->priority == pol->priority)
> + if (policy->mark.v == pol->mark.v &&
> + (policy->mark.m == pol->mark.m ||
> + policy->priority == pol->priority))
> return true;
>
> return false;
>
> which means we consider (the same value and mask) or
> (the same value and priority) as the same one. This will
> cover both problems.

policy A (mark.v = 0x1011, mark.m = 0x1011, priority = 1)
policy B (mark.v = 0x1001, mark.m = 0x1001, priority = 1)

when fl->flowi_mark == 0x12341011, in xfrm_policy_match() do check like this:

(fl->flowi_mark & pol->mark.m) != pol->mark.v

0x12341011 & 0x1011 == 0x00001011
0x12341011 & 0x1001 == 0x00001001

This also match different policy depends on the order of policy inserting.

>
> .
>

\
 
 \ /
  Last update: 2020-05-22 03:46    [W:0.120 / U:0.888 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site