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

From: David Ahern
Date: Tue Apr 25 2017 - 11:56:51 EST


On 3/4/17 11:57 AM, Dmitry Vyukov wrote:
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in rt6_dump_route+0x293/0x2f0
> net/ipv6/route.c:3551 at addr ffff88007e523694
> Read of size 4 by task syz-executor3/24426
> CPU: 2 PID: 24426 Comm: syz-executor3 Not tainted 4.10.0+ #293
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:16 [inline]
> dump_stack+0x2fb/0x3fd lib/dump_stack.c:52
> kasan_object_err+0x1c/0x90 mm/kasan/report.c:166
> print_address_description mm/kasan/report.c:208 [inline]
> kasan_report_error mm/kasan/report.c:292 [inline]
> kasan_report.part.2+0x1b0/0x460 mm/kasan/report.c:314
> kasan_report mm/kasan/report.c:334 [inline]
> __asan_report_load4_noabort+0x29/0x30 mm/kasan/report.c:334
> rt6_dump_route+0x293/0x2f0 net/ipv6/route.c:3551
> fib6_dump_node+0x101/0x1a0 net/ipv6/ip6_fib.c:315
> fib6_walk_continue+0x4b3/0x620 net/ipv6/ip6_fib.c:1576
> fib6_walk+0x91/0xf0 net/ipv6/ip6_fib.c:1621
> fib6_dump_table net/ipv6/ip6_fib.c:374 [inline]
> inet6_dump_fib+0x832/0xea0 net/ipv6/ip6_fib.c:447

My expectation is that this one is fixed with the ipv6 patch I have sent
(not yet committed). Are you seeing this backtrace with that patch?