All of lore.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+9fa589353c6e1587c6b3@syzkaller.appspotmail.com>
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com, tj@kernel.org
Subject: [syzbot] WARNING: suspicious RCU usage in kernfs_iop_get_link
Date: Fri, 11 Jun 2021 05:01:18 -0700	[thread overview]
Message-ID: <000000000000ec812705c47c4342@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    614124be Linux 5.13-rc5
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a6cdbbd00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=30f476588412c065
dashboard link: https://syzkaller.appspot.com/bug?extid=9fa589353c6e1587c6b3

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9fa589353c6e1587c6b3@syzkaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
5.13.0-rc5-syzkaller #0 Not tainted
-----------------------------
kernel/sched/core.c:8304 Illegal context switch in RCU-sched read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
no locks held by systemd-udevd/13755.

stack backtrace:
CPU: 0 PID: 13755 Comm: systemd-udevd Not tainted 5.13.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 ___might_sleep+0x266/0x2c0 kernel/sched/core.c:8304
 might_alloc include/linux/sched/mm.h:201 [inline]
 slab_pre_alloc_hook mm/slab.h:497 [inline]
 slab_alloc_node mm/slub.c:2834 [inline]
 slab_alloc mm/slub.c:2921 [inline]
 kmem_cache_alloc_trace+0x277/0x2c0 mm/slub.c:2938
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:686 [inline]
 kernfs_iop_get_link fs/kernfs/symlink.c:135 [inline]
 kernfs_iop_get_link+0x61/0x6e0 fs/kernfs/symlink.c:126
 pick_link fs/namei.c:1741 [inline]
 step_into+0x168e/0x1c80 fs/namei.c:1798
 open_last_lookups fs/namei.c:3308 [inline]
 path_openat+0x491/0x27e0 fs/namei.c:3491
 do_filp_open+0x190/0x3d0 fs/namei.c:3521
 do_sys_openat2+0x16d/0x420 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1207
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f0ff9316840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffeb81b55a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000701 RCX: 00007f0ff9316840
RDX: 0000000000000001 RSI: 0000000000080000 RDI: 00007ffeb81b55b0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000012
R10: 0000000000000064 R11: 0000000000000246 R12: 00007ffeb81b6600
R13: 00007ffeb81b7690 R14: 0000000000000000 R15: 0000000000000000


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

             reply	other threads:[~2021-06-11 12:01 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-11 12:01 syzbot [this message]
2021-06-11 12:08 ` [syzbot] WARNING: suspicious RCU usage in kernfs_iop_get_link Dmitry Vyukov

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=000000000000ec812705c47c4342@google.com \
    --to=syzbot+9fa589353c6e1587c6b3@syzkaller.appspotmail.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=tj@kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.