linux-kernel - [syzbot] WARNING: suspicious RCU usage in remove

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <00000000000019114805bf0fb1bc@google.com>
Date:   Sat, 03 Apr 2021 04:23:20 -0700
From:   syzbot <syzbot+26ad5e106ca477175819@...kaller.appspotmail.com>
To:     akpm@...ux-foundation.org, linux-kernel@...r.kernel.org,
        linux-mm@...ck.org, syzkaller-bugs@...glegroups.com
Subject: [syzbot] WARNING: suspicious RCU usage in remove_vma (2)

Hello,

syzbot found the following issue on:

HEAD commit:    1e43c377 Merge tag 'xtensa-20210329' of git://github.com/j..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1052e1d6d00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d1a3d65a48dbd1bc
dashboard link: https://syzkaller.appspot.com/bug?extid=26ad5e106ca477175819

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+26ad5e106ca477175819@...kaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
5.12.0-rc5-syzkaller #0 Not tainted
-----------------------------
kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
no locks held by syz-executor.0/29105.

stack backtrace:
CPU: 0 PID: 29105 Comm: syz-executor.0 Not tainted 5.12.0-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+0x229/0x2c0 kernel/sched/core.c:8294
 remove_vma+0x44/0x170 mm/mmap.c:178
 exit_mmap+0x33f/0x590 mm/mmap.c:3229
 __mmput+0x122/0x470 kernel/fork.c:1090
 mmput+0x58/0x60 kernel/fork.c:1111
 exit_mm kernel/exit.c:501 [inline]
 do_exit+0xb0a/0x2a60 kernel/exit.c:812
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2150 kernel/signal.c:2781
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
Code: Unable to access opcode bytes at RIP 0x46642f.
RSP: 002b:00007fdfaa117218 EFLAGS: 00000246
 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 000000000056bf68 RCX: 0000000000466459
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007fff64c569cf R14: 00007fdfaa117300 R15: 0000000000022000


---
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@...glegroups.com.

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