[v5.15] INFO: rcu detected stall in sys_getsockopt

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8a1d809b0545 Linux 5.15.142
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15cbc8aee80000
kernel config: https://syzkaller.appspot.com/x/.config?x=ee92f7141049e8f2
dashboard link: https://syzkaller.appspot.com/bug?extid=8ea796d5925941ba12f6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8965895d90e2/disk-8a1d809b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f8d2c2cd9799/vmlinux-8a1d809b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4fa328be23e7/bzImage-8a1d809b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8ea796...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4217/1:b..l P3735/1:b..l P6372/1:b..l
(detected by 1, t=10502 jiffies, g=59421, q=105)
task:syz-executor.1 state:R running task stack:20960 pid: 6372 ppid: 6371 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:426
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 dc 5e 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90004b56d60 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200096adb8 RCX: 1ffff9200096ad58
RDX: dffffc0000000000 RSI: ffffffff8a8b2000 RDI: ffffffff8ad87dc0
RBP: ffffc90004b56ea8 R08: dffffc0000000000 R09: fffffbfff1f79e19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200096adb4
R13: dffffc0000000000 R14: ffffc90004b56dc0 R15: 0000000000000246
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
rcu_read_lock include/linux/rcupdate.h:696 [inline]
net_generic+0x1b/0x200 include/net/netns/generic.h:44
find_inlist_lock_noload+0x39/0x260 net/bridge/netfilter/ebtables.c:324
find_inlist_lock net/bridge/netfilter/ebtables.c:370 [inline]
find_table_lock net/bridge/netfilter/ebtables.c:379 [inline]
do_ebt_get_ctl+0x3cb/0x28e0 net/bridge/netfilter/ebtables.c:2461
nf_getsockopt+0x28e/0x2b0 net/netfilter/nf_sockopt.c:116
ip_getsockopt+0x136c/0x1ec0 net/ipv4/ip_sockglue.c:1787
tcp_getsockopt+0x26d/0x6c20 net/ipv4/tcp.c:4293
__sys_getsockopt+0x2a6/0x550 net/socket.c:2240
__do_sys_getsockopt net/socket.c:2255 [inline]
__se_sys_getsockopt net/socket.c:2252 [inline]
__x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2252
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7faa6b7ed74a
RSP: 002b:00007fff93b89278 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007faa6b8e5ea0 RCX: 00007faa6b7ed74a
RDX: 0000000000000080 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fff93b8929c R09: 00007fff93b896a7
R10: 00007fff93b892a0 R11: 0000000000000246 R12: 00007fff93b892a0
R13: 00007fff93b8929c R14: 0000000000000002 R15: 0000000000000000
</TASK>
task:kworker/u4:11 state:R running task stack:20152 pid: 3735 ppid: 2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_notrace+0xf8/0x140 kernel/sched/core.c:6631
preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
rcu_is_watching+0x72/0xa0 kernel/rcu/tree.c:1124
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0xdd/0x4f0 kernel/locking/lockdep.c:5594
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
rcu_read_lock include/linux/rcupdate.h:696 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline]
batadv_iv_ogm_schedule+0x429/0x1000 net/batman-adv/bat_iv_ogm.c:869
batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>
task:kworker/u4:17 state:R running task stack:23320 pid: 4217 ppid: 2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:426
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 dc 5e 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90002df78e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920005bef28 RCX: 1ffff920005beec8
RDX: dffffc0000000000 RSI: ffffffff8a8b2000 RDI: ffffffff8ad87dc0
RBP: ffffc90002df7a40 R08: dffffc0000000000 R09: fffffbfff1f79e19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920005bef24
R13: dffffc0000000000 R14: ffffc90002df7940 R15: 0000000000000246
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
rcu_read_lock include/linux/rcupdate.h:696 [inline]
inet_twsk_purge+0x11e/0xa20 net/ipv4/inet_timewait_sock.c:268
ops_exit_list net/core/net_namespace.c:174 [inline]
cleanup_net+0x763/0xb60 net/core/net_namespace.c:596
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.