netdev - Re: [PATCH] cls_rsvp: add sanity check for the packet length

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Wed, 4 Aug 2010 21:52:53 +0800
From:	Changli Gao <xiaosuo@...il.com>
To:	hadi@...erus.ca
Cc:	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH] cls_rsvp: add sanity check for the packet length

On Wed, Aug 4, 2010 at 9:44 PM, Changli Gao <xiaosuo@...il.com> wrote:
> On Wed, Aug 4, 2010 at 9:42 PM, jamal <hadi@...erus.ca> wrote:
>> On Wed, 2010-08-04 at 16:55 +0800, Changli Gao wrote:
>>> The packet length should be checked before the packet data is dereferenced.
>>>
>>> Signed-off-by: Changli Gao <xiaosuo@...il.com>
>>> ---
>>>  net/sched/cls_rsvp.h |   10 +++++++++-
>>>  1 file changed, 9 insertions(+), 1 deletion(-)
>>> diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
>>> index dd9414e..4fa119d 100644
>>> --- a/net/sched/cls_rsvp.h
>>> +++ b/net/sched/cls_rsvp.h
>>> @@ -143,9 +143,17 @@ static int rsvp_classify(struct sk_buff *skb, struct tcf_proto *tp,
>>>       u8 tunnelid = 0;
>>>       u8 *xprt;
>>>  #if RSVP_DST_LEN == 4
>>> -     struct ipv6hdr *nhptr = ipv6_hdr(skb);
>>> +     struct ipv6hdr *nhptr;
>>> +
>>> +     if (!pskb_may_pull(skb, skb_network_offset(skb) + sizeof(*nhptr)))
>>> +             return -1;
>>> +     nhptr = ipv6_hdr(skb);
>>>  #else
>>>       struct iphdr *nhptr = ip_hdr(skb);
>>> +
>>> +     if (!pskb_may_pull(skb, skb_network_offset(skb) + sizeof(*nhptr)))
>>> +             return -1;
>>> +     nhptr = ip_hdr(skb);
>>>  #endif
>>
>> Maybe a good time to move nhptr declaration outside #if since it is used
>> in #else as well.
>>
>
> They are not the same type. I am afraid that it won't work.
>

I'll respin it with the routine pskb_network_may_pull(). Thanks.

-- 
Regards,
Changli Gao(xiaosuo@...il.com)
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html