======================================================
WARNING: possible circular locking dependency detected
6.1.128-syzkaller #0 Not tainted
------------------------------------------------------
syz.2.4697/17968 is trying to acquire lock:
ffff8880b8f28118 (krc.lock){-.-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2991 [inline]
ffff8880b8f28118 (krc.lock){-.-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3311 [inline]
ffff8880b8f28118 (krc.lock){-.-.}-{2:2}, at: kvfree_call_rcu+0x1b2/0x8c0 kernel/rcu/tree.c:3402
but task is already holding lock:
ffff8880b8f2a4d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1693 [inline]
ffff8880b8f2a4d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x6d3/0xe50 kernel/time/hrtimer.c:1753
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (hrtimer_bases.lock){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
lock_hrtimer_base kernel/time/hrtimer.c:174 [inline]
hrtimer_start_range_ns+0x105/0xc80 kernel/time/hrtimer.c:1300
hrtimer_start include/linux/hrtimer.h:420 [inline]
run_page_cache_worker kernel/rcu/tree.c:3293 [inline]
kvfree_call_rcu+0x72b/0x8c0 kernel/rcu/tree.c:3404
rtnl_register_internal+0x489/0x580 net/core/rtnetlink.c:260
rtnl_register+0x32/0x70 net/core/rtnetlink.c:310
ip_rt_init+0x335/0x3c7 net/ipv4/route.c:3763
ip_init+0xa/0x14 net/ipv4/ip_output.c:1770
inet_init+0x2ae/0x3c0 net/ipv4/af_inet.c:2033
do_one_initcall+0x265/0x8f0 init/main.c:1298
do_initcall_level+0x157/0x207 init/main.c:1371
do_initcalls+0x49/0x86 init/main.c:1387
kernel_init_freeable+0x45c/0x60f init/main.c:1626
kernel_init+0x19/0x290 init/main.c:1514
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
-> #0 (krc.lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2991 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3311 [inline]
kvfree_call_rcu+0x1b2/0x8c0 kernel/rcu/tree.c:3402
trie_delete_elem+0x53a/0x690 kernel/bpf/lpm_trie.c:545
bpf_prog_2c29ac5cdc6b1842+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2323
trace_hrtimer_start include/trace/events/timer.h:202 [inline]
debug_activate kernel/time/hrtimer.c:477 [inline]
enqueue_hrtimer+0x382/0x410 kernel/time/hrtimer.c:1085
__run_hrtimer kernel/time/hrtimer.c:1706 [inline]
__hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1753
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
lockdep_unregister_key+0x562/0x600 kernel/locking/lockdep.c:6367
__qdisc_destroy+0x127/0x450 net/sched/sch_generic.c:1078
netdev_for_each_tx_queue include/linux/netdevice.h:2465 [inline]
dev_shutdown+0x9d/0x440 net/sched/sch_generic.c:1489
unregister_netdevice_many+0xaac/0x17a0 net/core/dev.c:10938
unregister_netdevice_queue+0x2e6/0x350 net/core/dev.c:10878
unregister_netdevice include/linux/netdevice.h:3067 [inline]
__tun_detach+0x6b6/0x1600 drivers/net/tun.c:685
tun_detach drivers/net/tun.c:701 [inline]
tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3492
__fput+0x3f6/0x8d0 fs/file_table.c:320
task_work_run+0x246/0x300 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hrtimer_bases.lock);
lock(krc.lock);
lock(hrtimer_bases.lock);
lock(krc.lock);
*** DEADLOCK ***
3 locks held by syz.2.4697/17968:
#0: ffffffff8e50bfa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8e50bfa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492
#1: ffff8880b8f2a4d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1693 [inline]
#1: ffff8880b8f2a4d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x6d3/0xe50 kernel/time/hrtimer.c:1753
#2: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#2: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#2: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline]
#2: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x110/0x410 kernel/trace/bpf_trace.c:2323
stack backtrace:
CPU: 1 PID: 17968 Comm: syz.2.4697 Not tainted 6.1.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2991 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3311 [inline]
kvfree_call_rcu+0x1b2/0x8c0 kernel/rcu/tree.c:3402
trie_delete_elem+0x53a/0x690 kernel/bpf/lpm_trie.c:545
bpf_prog_2c29ac5cdc6b1842+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2323
trace_hrtimer_start include/trace/events/timer.h:202 [inline]
debug_activate kernel/time/hrtimer.c:477 [inline]
enqueue_hrtimer+0x382/0x410 kernel/time/hrtimer.c:1085
__run_hrtimer kernel/time/hrtimer.c:1706 [inline]
__hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1753
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lockdep_unregister_key+0x562/0x600 kernel/locking/lockdep.c:6367
Code: 20 91 48 c7 c6 f0 f2 6a 81 e8 aa b3 08 00 e8 e5 c7 08 00 e9 ea fb ff ff e8 6b e3 47 09 41 f7 c7 00 02 00 00 74 d0 fb 45 84 f6 <75> cf eb e0 0f 0b 45 31 f6 e9 64 ff ff ff 0f 0b e9 a5 fe ff ff 0f
RSP: 0018:ffffc900035178e0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 1ffff920006a2f24 RCX: ffffffff97357103
RDX: 0000000000000001 RSI: ffffffff8b0c1020 RDI: ffffffff8b5e6980
RBP: ffffc900035179c0 R08: dffffc0000000000 R09: fffffbfff2240308
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90003517920
R13: 1ffff920006a2f20 R14: 0000000000000000 R15: 0000000000000a06
__qdisc_destroy+0x127/0x450 net/sched/sch_generic.c:1078
netdev_for_each_tx_queue include/linux/netdevice.h:2465 [inline]
dev_shutdown+0x9d/0x440 net/sched/sch_generic.c:1489
unregister_netdevice_many+0xaac/0x17a0 net/core/dev.c:10938
unregister_netdevice_queue+0x2e6/0x350 net/core/dev.c:10878
unregister_netdevice include/linux/netdevice.h:3067 [inline]
__tun_detach+0x6b6/0x1600 drivers/net/tun.c:685
tun_detach drivers/net/tun.c:701 [inline]
tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3492
__fput+0x3f6/0x8d0 fs/file_table.c:320
task_work_run+0x246/0x300 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb6a038cde9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdffbc5cc8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fb6a05a7ba0 RCX: 00007fb6a038cde9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fb6a05a7ba0 R08: 00000000000002f8 R09: 0000000effbc5fbf
R10: 00000000003ffae4 R11: 0000000000000246 R12: 00000000000e0010
R13: 00007fb6a05a6240 R14: ffffffffffffffff R15: 00007ffdffbc5de0
----------------
Code disassembly (best guess):
0: 20 91 48 c7 c6 f0 and %dl,-0xf3938b8(%rcx)
6: f2 6a 81 repnz push $0xffffffffffffff81
9: e8 aa b3 08 00 call 0x8b3b8
e: e8 e5 c7 08 00 call 0x8c7f8
13: e9 ea fb ff ff jmp 0xfffffc02
18: e8 6b e3 47 09 call 0x947e388
1d: 41 f7 c7 00 02 00 00 test $0x200,%r15d
24: 74 d0 je 0xfffffff6
26: fb sti
27: 45 84 f6 test %r14b,%r14b
* 2a: 75 cf jne 0xfffffffb <-- trapping instruction
2c: eb e0 jmp 0xe
2e: 0f 0b ud2
30: 45 31 f6 xor %r14d,%r14d
33: e9 64 ff ff ff jmp 0xffffff9c
38: 0f 0b ud2
3a: e9 a5 fe ff ff jmp 0xfffffee4
3f: 0f .byte 0xf