Subject: Re: INFO: rcu detected stall in is_bpf_text_address

From: Marcelo Ricardo Leitner <[email-masked]>
Date: Mon, 28 May 2018 15:22:31 -0300

On Sun, May 20, 2018 at 04:26:03PM +0800, Xin Long wrote:
> On Sat, May 19, 2018 at 11:57 PM, Eric Dumazet <[email-masked]> wrote:
> > SCTP experts, please take a look.
> >
> > On 05/19/2018 08:55 AM, syzbot wrote:
> >> Hello,
> >>
> >> syzbot found the following crash on:
> >>
> >> HEAD commit:    73fcb1a370c7 Merge branch 'akpm' (patches from Andrew)
> >> git tree:       upstream
> >> console output: https://syzkaller.appspot.com/x/log.txt?x=1462ec0f800000
> >> kernel config:  https://syzkaller.appspot.com/x/.config?x=f3b4e30da84ec1ed
> >> dashboard link: https://syzkaller.appspot.com/bug?extid=3dcd59a1f907245f891f
> >> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> >> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1079cf8f800000

The reproducer has:
r0 = socket$inet6(0xa, 0x1, 0x8010000000000084)

Considering socket() prototype uses an int for the 3rd argument, how
should I interpret this 64b value?

0x84 is IPPROTO_SCTP, but don't know about the 0x8010000000000000 in
there.