From: Alan Stern <stern@rowland.harvard.edu>
To: syzbot <syzbot+2eb9121678bdb36e6d57@syzkaller.appspotmail.com>
Cc: andreyknvl@google.com, <gregkh@linuxfoundation.org>,
Kernel development list <linux-kernel@vger.kernel.org>,
USB list <linux-usb@vger.kernel.org>, <rafael@kernel.org>,
<syzkaller-bugs@googlegroups.com>
Subject: Re: general protection fault in __dev_printk
Date: Mon, 22 Apr 2019 13:53:17 -0400 (EDT) [thread overview]
Message-ID: <Pine.LNX.4.44L0.1904221344550.1384-100000@iolanthe.rowland.org> (raw)
In-Reply-To: <00000000000029431d0586d10813@google.com>
On Thu, 18 Apr 2019, syzbot wrote:
> syzbot has found a reproducer for the following crash on:
>
> HEAD commit: d34f9519 usb-fuzzer: main usb gadget fuzzer driver
> git tree: https://github.com/google/kasan/tree/usb-fuzzer
> console output: https://syzkaller.appspot.com/x/log.txt?x=10adfe6b200000
> kernel config: https://syzkaller.appspot.com/x/.config?x=c73d1bb5aeaeae20
> dashboard link: https://syzkaller.appspot.com/bug?extid=2eb9121678bdb36e6d57
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=145cb7e3200000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f8bd2d200000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+2eb9121678bdb36e6d57@syzkaller.appspotmail.com
>
> yurex 1-1:0.150: yurex_interrupt - unknown status received: -71
> usb 1-1: USB disconnect, device number 112
> yurex 1-1:0.150: yurex_interrupt - unknown status received: -71
> 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 PTI
Andrey:
This original bug report included a "USB disconnect" line, as shown
above. The newer results, for runs with my patches added, do not. At
least, if such a line was present, it didn't show up in the console
output files -- the most recent one contains nothing but repeats of
that "yurex_interrupt - unknown status received: -71" line, although
for devices on multiple buses.
Is there any way to get more information about what's happening, such
as a complete kernel log? And perhaps to run the test with just a
single dummy-hcd bus instead of 6?
At this point, I suspect the original general protection fault in
the yurex driver has been fixed, but something else in dummy-hcd may be
causing the rcu-detected stalls.
Alan Stern
next prev parent reply other threads:[~2019-04-22 17:53 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-17 11:26 general protection fault in __dev_printk syzbot
2019-04-18 17:07 ` syzbot
2019-04-19 20:44 ` Alan Stern
2019-04-19 21:22 ` syzbot
2019-04-22 15:39 ` Alan Stern
2019-04-22 15:55 ` syzbot
2019-04-22 16:07 ` Alan Stern
2019-04-22 16:44 ` syzbot
2019-04-22 17:53 ` Alan Stern [this message]
2019-04-23 15:05 ` Andrey Konovalov
2019-04-23 15:28 ` Alan Stern
2019-04-23 16:06 ` syzbot
2019-04-23 16:46 ` Alan Stern
2019-04-23 17:24 ` syzbot
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=Pine.LNX.4.44L0.1904221344550.1384-100000@iolanthe.rowland.org \
--to=stern@rowland.harvard.edu \
--cc=andreyknvl@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=rafael@kernel.org \
--cc=syzbot+2eb9121678bdb36e6d57@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).