linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
To: syzbot <syzbot+bcad772bbc241b4c6147@syzkaller.appspotmail.com>,
	syzkaller-bugs@googlegroups.com, Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>
Cc: jmorris@namei.org, linux-kernel@vger.kernel.org,
	linux-security-module@vger.kernel.org, serge@hallyn.com
Subject: Re: INFO: rcu detected stall in sys_sendfile64
Date: Wed, 19 Dec 2018 19:11:58 +0900	[thread overview]
Message-ID: <a5478450-f975-228f-1ca6-886a45b654a1@I-love.SAKURA.ne.jp> (raw)
In-Reply-To: <000000000000e728ec057d5c9d90@google.com>

On 2018/12/19 18:27, syzbot wrote:
> HEAD commit:    ddfbab46539f Merge tag 'scsi-fixes' of git://git.kernel.or..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=15b87fa3400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=861a3573f4e78ba1
> dashboard link: https://syzkaller.appspot.com/bug?extid=bcad772bbc241b4c6147
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13912ccd400000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=145781db400000

This is not a LSM problem, for the reproducer is calling
sched_setattr(SCHED_DEADLINE) with very large values.

  sched_setattr(0, {size=0, sched_policy=0x6 /* SCHED_??? */, sched_flags=0, sched_nice=0, sched_priority=0, sched_runtime=2251799813724439, sched_deadline=4611686018427453437, sched_period=0}, 0) = 0

I think that this problem is nothing but an insane sched_setattr() parameter.

#syz invalid


  reply	other threads:[~2018-12-19 10:13 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-19  9:27 INFO: rcu detected stall in sys_sendfile64 syzbot
2018-12-19 10:11 ` Tetsuo Handa [this message]
2018-12-19 18:42   ` Dmitry Vyukov
2020-01-04 11:09     ` Tetsuo Handa
2020-01-07 13:02       ` Dmitry Vyukov
2020-01-07 13:11         ` Peter Zijlstra

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=a5478450-f975-228f-1ca6-886a45b654a1@I-love.SAKURA.ne.jp \
    --to=penguin-kernel@i-love.sakura.ne.jp \
    --cc=jmorris@namei.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=serge@hallyn.com \
    --cc=syzbot+bcad772bbc241b4c6147@syzkaller.appspotmail.com \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).