Re: net: heap out-of-bounds in fib6_clean_node/rt6_fill_node/fib6_age/fib6_prune_clone

From: David Ahern
Date: Tue Apr 18 2017 - 19:20:41 EST


On 4/18/17 2:43 PM, Andrey Konovalov wrote:
> I've finally managed to reproduce one of the crashes on commit
> 4f7d029b9bf009fbee76bb10c0c4351a1870d2f3 (4.11-rc7).
>
> I'm not sure if this bug has the same root cause as the first one
> reported in this thread, but it definitely has to do with ipv6
> routing.
>
> C reproducer, syzkaller program and my .config are attached.
>
> Thanks!
>
> kasan: CONFIG_KASAN_INLINE enabled
> kasan: GPF could be caused by NULL-ptr deref or user memory access
> general protection fault: 0000 [#1] SMP KASAN
> Modules linked in:
> CPU: 1 PID: 4035 Comm: a.out Not tainted 4.11.0-rc7+ #250
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> task: ffff880069809600 task.stack: ffff880062dc8000
> RIP: 0010:ip6_rt_cache_alloc+0xa6/0x560 net/ipv6/route.c:975

>From a quick glance seems to be a different bug than Dmitry's.