Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1527825

Re: net/icmp: null-ptr-deref in icmp6_send

Show all headers | View raw

On Tue, Nov 22, 2016 at 2:23 AM, Andrey Konovalov <andreyknvl@google.com> wrote:
> Hi,
>
> I've got the following error report while fuzzing the kernel with syzkaller.
>
> It seems that skb_dst(skb) may end up being NULL.
>
> As far as I can see the bug was introduced in commit 5d41ce29e ("net:
> icmp6_send should use dst dev to determine L3 domain").
> ICMP v4 probaly has similar issue due to 9d1a6c4ea ("net:
> icmp_route_lookup should use rt dev to determine L3 domain").


ipv6_parse_hopopts() is called before NF_INET_PRE_ROUTING,
so the skb_dst could be NULL.

I have no idea what commit 5d41ce29e tried to fix, but we already
use skb->dev a few lines before l3mdev_master_ifindex(), so I don't
understand why skb->dev could be NULL, maybe just for vrf dev?

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

net/icmp: null-ptr-deref in icmp6_send Andrey Konovalov <andreyknvl@google.com> - 2016-11-22 11:30 +0100
  Re: net/icmp: null-ptr-deref in icmp6_send Cong Wang <xiyou.wangcong@gmail.com> - 2016-11-22 19:20 +0100
    Re: net/icmp: null-ptr-deref in icmp6_send David Ahern <dsa@cumulusnetworks.com> - 2016-11-22 20:20 +0100
    Re: net/icmp: null-ptr-deref in icmp6_send David Ahern <dsa@cumulusnetworks.com> - 2016-11-23 04:20 +0100

csiph-web