WARNING in task_participate_group

WARNING in task_participate_group_stop (2)
Status: upstream: reported C repro on 2018/04/29 17:00
Reported-by: syzbot+b109633ea805cac54a61@syzkaller.appspotmail.com
First crash: 949d, last: 225d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: WARNING in corrupted (log)
Repro: C syz .config

Fix bisection: fixed by (bisect log) [merge commit]:
commit c32beba325d8c54d8affa158a0a54643ba87eab4
Author: Olof Johansson <olof@lixom.net>
Date: Thu May 16 06:23:43 2019 +0000

Merge tag 'mvebu-arm-5.2-1' of git://git.infradead.org/linux-mvebu into arm/late

similar bugs (8):
Kernel	Title	Repro	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.14	WARNING in task_participate_group_stop	C	inconclusive	2	176d	366d	0/1	upstream: reported C repro on 2019/12/02 14:36
android-414	WARNING in task_participate_group_stop	C		2	637d	601d	0/1	public: reported C repro on 2019/04/12 00:01
android-44	WARNING in task_participate_group_stop (2)	C		4	637d	600d	0/2	public: reported C repro on 2019/04/13 00:00
android-49	WARNING in task_participate_group_stop	C		15	1057d	1214d	2/3	fixed on 2018/02/06 12:55
upstream	WARNING in task_participate_group_stop	C		29	1114d	1129d	4/17	fixed on 2018/02/02 04:39
linux-4.19	WARNING in task_participate_group_stop	C	error	2	218d	366d	0/1	upstream: reported C repro on 2019/12/02 13:46
android-44	WARNING in task_participate_group_stop	C		10	1066d	1073d	2/2	fixed on 2018/02/06 10:09
android-49	WARNING in task_participate_group_stop (2)	C		11	366d	599d	0/3	public: reported C repro on 2019/04/14 00:00

Sample crash report:

IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_hsr: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready
8021q: adding VLAN 0 to HW filter on device batadv0
8021q: adding VLAN 0 to HW filter on device batadv0
8021q: adding VLAN 0 to HW filter on device batadv0
WARNING: CPU: 0 PID: 7729 at kernel/signal.c:368 task_participate_group_stop+0x200/0x260 kernel/signal.c:368
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 7729 Comm: 3 Not tainted 5.0.0+ #8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2cb/0x65c kernel/panic.c:214
 __warn.cold+0x20/0x45 kernel/panic.c:571
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:task_participate_group_stop+0x200/0x260 kernel/signal.c:368
Code: d0 7c 04 84 d2 75 61 41 89 9d a4 00 00 00 41 bc 01 00 00 00 e9 59 ff ff ff e8 fc 68 29 00 0f 0b e9 91 fe ff ff e8 f0 68 29 00 <0f> 0b e9 fe fe ff ff 4c 89 e7 e8 b1 03 61 00 e9 ca fe ff ff e8 d7
RSP: 0018:ffff8880989bfc18 EFLAGS: 00010093
RAX: ffff88809b8d41c0 RBX: 0000000000000000 RCX: ffffffff8146825e
RDX: 0000000000000000 RSI: ffffffff81468370 RDI: 0000000000000005
RBP: ffff8880989bfc38 R08: ffff88809b8d41c0 R09: ffffed1013137f83
R10: ffffed1013137f82 R11: 0000000000000003 R12: ffff8880a970f7e0
R13: ffff8880a970f740 R14: 0000000000040000 R15: dffffc0000000000
 do_signal_stop+0x1e6/0x840 kernel/signal.c:2265
 get_signal+0xd72/0x1d50 kernel/signal.c:2450
 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x3000000
Code: Bad RIP value.
RSP: 002b:00007ffe65724950 EFLAGS: 00000200 ORIG_RAX: 000000000000003b
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (15):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	Maintainers
ci-upstream-kasan-gce	2019/03/06 18:53	upstream	3717f613	05cf83bf	.config	log	report	syz	C	akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-root	2019/03/06 18:52	upstream	3717f613	05cf83bf	.config	log	report	syz	C	akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-root	2018/04/29 02:26	upstream	bf8f5de1	d5a5d045	.config	log	report	syz	C	akpm@linux-foundation.org, ebiederm@xmission.com, ldv@altlinux.org, linux-kernel@vger.kernel.org, linux@dominikbrodowski.net, oleg@redhat.com, viro@zeniv.linux.org.uk
ci-upstream-kasan-gce	2018/04/28 22:08	upstream	a97d8efd	d5a5d045	.config	log	report	syz	C	akpm@linux-foundation.org, ebiederm@xmission.com, ldv@altlinux.org, linux-kernel@vger.kernel.org, linux@dominikbrodowski.net, oleg@redhat.com, viro@zeniv.linux.org.uk
ci-upstream-kasan-gce	2020/03/29 01:46	upstream	906c4043	05736b29	.config	log	report	syz		christian@brauner.io, ebiederm@xmission.com, guro@fb.com, linux-kernel@vger.kernel.org, oleg@redhat.com
ci-upstream-kasan-gce-root	2019/12/03 10:35	upstream	596cf45c	ab342da3	.config	log	report	syz		arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, guro@fb.com, linux-kernel@vger.kernel.org, oleg@redhat.com
ci-upstream-kasan-gce	2019/12/02 14:55	upstream	ceb30747	f879db37	.config	log	report	syz		arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, guro@fb.com, linux-kernel@vger.kernel.org, oleg@redhat.com, tj@kernel.org
ci-upstream-kasan-gce-selinux-root	2019/03/06 19:46	upstream	3717f613	05cf83bf	.config	log	report	syz		akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-smack-root	2019/03/06 18:47	upstream	3717f613	05cf83bf	.config	log	report	syz		akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-386	2019/12/02 15:34	upstream	ceb30747	f879db37	.config	log	report	syz		akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, guro@fb.com, linux-kernel@vger.kernel.org, oleg@redhat.com
ci-upstream-kasan-gce-386	2019/03/06 18:46	upstream	3717f613	05cf83bf	.config	log	report	syz		akpm@linux-foundation.org, arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, tglx@linutronix.de
ci-upstream-kasan-gce-386	2018/05/02 13:48	upstream	f2125992	d5b114b4	.config	log	report	syz		akpm@linux-foundation.org, ebiederm@xmission.com, ldv@altlinux.org, linux-kernel@vger.kernel.org, linux@dominikbrodowski.net, oleg@redhat.com, viro@zeniv.linux.org.uk
ci-upstream-linux-next-kasan-gce-root	2020/04/21 08:59	linux-next	ac935d22	98a9f9e6	.config	log	report	syz		christian@brauner.io, ebiederm@xmission.com, linux-kernel@vger.kernel.org, oleg@redhat.com
ci-upstream-kasan-gce	2020/01/30 16:06	upstream	39bed42d	5ed23f9a	.config	log	report			christian@brauner.io, ebiederm@xmission.com, linux-kernel@vger.kernel.org, oleg@redhat.com
ci-upstream-kasan-gce-selinux-root	2018/10/07 07:37	upstream	c1d84a1b	8b311eaf	.config	log	report			akpm@linux-foundation.org, anna-maria@linutronix.de, christian@brauner.io, ebiederm@xmission.com, linux-kernel@vger.kernel.org, oleg@redhat.com