Re: INFO: rcu detected stall in corrupted

From: Eric Dumazet
Date: Mon May 21 2018 - 13:19:09 EST




On 05/21/2018 11:09 AM, David Miller wrote:
> From: syzbot <syzbot+f116bc1994efe725d51b@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Date: Mon, 21 May 2018 11:05:02 -0700
>
>> find_match+0x244/0x13a0 net/ipv6/route.c:691
>> find_rr_leaf net/ipv6/route.c:729 [inline]
>> rt6_select net/ipv6/route.c:779 [inline]
>
> Hmmm, endless loop in find_rr_leaf or similar?
>


I do not think so, this really looks like SCTP specific
, we now have dozens of traces all sharing :

sctp_transport_route+0xad/0x450 net/sctp/transport.c:293
sctp_packet_config+0xb89/0xfd0 net/sctp/output.c:123
sctp_outq_flush+0x79c/0x4370 net/sctp/outqueue.c:894
sctp_outq_uncork+0x6a/0x80 net/sctp/outqueue.c:776
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1820 [inline]
sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline]
sctp_do_sm+0x596/0x7160 net/sctp/sm_sideeffect.c:1191
sctp_generate_heartbeat_event+0x218/0x450 net/sctp/sm_sideeffect.c:406
call_timer_fn+0x230/0x940 kernel/time/timer.c:1326


Some kind of infinite loop.

When the hrtimer fires, it can point to any code that sits below but does not necessarily have a bug.