======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.63/4480 is trying to acquire lock:
ffff88807b0eb238 (&trie->lock){-.-.}-{2:2}, at: trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
but task is already holding lock:
ffff8880b912a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
ffff8880b912a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5a2/0xb70 kernel/time/hrtimer.c:1749
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (hrtimer_bases.lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
lock_hrtimer_base kernel/time/hrtimer.c:168 [inline]
hrtimer_start_range_ns+0xff/0xc20 kernel/time/hrtimer.c:1284
hrtimer_start include/linux/hrtimer.h:420 [inline]
run_page_cache_worker kernel/rcu/tree.c:3492 [inline]
kvfree_call_rcu+0x61b/0x7d0 kernel/rcu/tree.c:3603
rtnl_register_internal+0x489/0x590 net/core/rtnetlink.c:225
rtnl_register+0x2e/0x70 net/core/rtnetlink.c:275
ip_rt_init+0x2e0/0x3a0 net/ipv4/route.c:3803
ip_init+0xa/0x20 net/ipv4/ip_output.c:1749
inet_init+0x28b/0x3a0 net/ipv4/af_inet.c:2007
do_one_initcall+0x272/0x730 init/main.c:1316
do_initcall_level+0x137/0x1f0 init/main.c:1389
do_initcalls+0x4b/0x90 init/main.c:1405
kernel_init_freeable+0x3e9/0x570 init/main.c:1629
kernel_init+0x19/0x1b0 init/main.c:1520
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #1 (krc.lock){..-.}-{2:2}:
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:3203 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3510 [inline]
kvfree_call_rcu+0x18d/0x7d0 kernel/rcu/tree.c:3601
trie_update_elem+0x86c/0xc50 kernel/bpf/lpm_trie.c:396
bpf_map_update_value+0x57d/0x650 kernel/bpf/syscall.c:223
generic_map_update_batch+0x52d/0x7d0 kernel/bpf/syscall.c:1430
bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1
__sys_bpf+0x671/0x6f0 kernel/bpf/syscall.c:-1
__do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (&trie->lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
bpf_prog_d46ba5bef82912c0+0x3d/0x97c
bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
bpf_trace_run2+0x163/0x2e0 kernel/trace/bpf_trace.c:1915
trace_hrtimer_start include/trace/events/timer.h:199 [inline]
debug_activate kernel/time/hrtimer.c:466 [inline]
enqueue_hrtimer+0x314/0x370 kernel/time/hrtimer.c:1069
__run_hrtimer kernel/time/hrtimer.c:1702 [inline]
__hrtimer_run_queues+0x5f3/0xb70 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
stack_access_ok arch/x86/kernel/unwind_orc.c:347 [inline]
deref_stack_reg arch/x86/kernel/unwind_orc.c:357 [inline]
unwind_next_frame+0x924/0x1d90 arch/x86/kernel/unwind_orc.c:539
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3225 [inline]
slab_alloc mm/slub.c:3233 [inline]
kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
kmem_cache_zalloc include/linux/slab.h:728 [inline]
__kernfs_new_node+0xe3/0x6c0 fs/kernfs/dir.c:593
kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:669
__kernfs_create_file+0x47/0x2e0 fs/kernfs/file.c:985
sysfs_add_file_mode_ns+0x2d4/0x3a0 fs/sysfs/file.c:317
create_files fs/sysfs/group.c:64 [inline]
internal_create_group+0x495/0xd00 fs/sysfs/group.c:149
internal_create_groups fs/sysfs/group.c:189 [inline]
sysfs_create_groups+0x55/0x120 fs/sysfs/group.c:215
create_dir lib/kobject.c:100 [inline]
kobject_add_internal+0x82c/0xd90 lib/kobject.c:263
kobject_add_varg lib/kobject.c:398 [inline]
kobject_init_and_add+0x128/0x190 lib/kobject.c:481
netdev_queue_add_kobject net/core/net-sysfs.c:1666 [inline]
netdev_queue_update_kobjects+0x19c/0x3e0 net/core/net-sysfs.c:1711
register_queue_kobjects net/core/net-sysfs.c:1772 [inline]
netdev_register_kobject+0x273/0x320 net/core/net-sysfs.c:2018
register_netdevice+0x1039/0x16f0 net/core/dev.c:10397
__ip_tunnel_create+0x2c7/0x390 net/ipv4/ip_tunnel.c:267
ip_tunnel_init_net+0x246/0x6f0 net/ipv4/ip_tunnel.c:1084
vti_init_net+0x2b/0xf0 net/ipv4/ip_vti.c:504
ops_init+0x357/0x600 net/core/net_namespace.c:138
setup_net+0x39e/0xa10 net/core/net_namespace.c:333
copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178
copy_process+0x1834/0x3e20 kernel/fork.c:2293
kernel_clone+0x23f/0x990 kernel/fork.c:2679
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x19a/0x210 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
other info that might help us debug this:
Chain exists of:
&trie->lock --> krc.lock --> hrtimer_bases.lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hrtimer_bases.lock);
lock(krc.lock);
lock(hrtimer_bases.lock);
lock(&trie->lock);
*** DEADLOCK ***
4 locks held by syz.3.63/4480:
#0: ffffffff8d428b90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
#1: ffffffff8d434808 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x234/0x6f0 net/ipv4/ip_tunnel.c:1083
#2: ffff8880b912a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
#2: ffff8880b912a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5a2/0xb70 kernel/time/hrtimer.c:1749
#3: ffffffff8c31c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
stack backtrace:
CPU: 1 PID: 4480 Comm: syz.3.63 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
bpf_prog_d46ba5bef82912c0+0x3d/0x97c
bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
bpf_trace_run2+0x163/0x2e0 kernel/trace/bpf_trace.c:1915
trace_hrtimer_start include/trace/events/timer.h:199 [inline]
debug_activate kernel/time/hrtimer.c:466 [inline]
enqueue_hrtimer+0x314/0x370 kernel/time/hrtimer.c:1069
__run_hrtimer kernel/time/hrtimer.c:1702 [inline]
__hrtimer_run_queues+0x5f3/0xb70 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:347 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:357 [inline]
RIP: 0010:unwind_next_frame+0x924/0x1d90 arch/x86/kernel/unwind_orc.c:539
Code: f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 d5 0e 89 00 4c 89 7c 24 60 4c 8b 73 08 48 8d 7b 10 48 89 f8 48 c1 e8 03 42 80 3c 28 00 <74> 05 e8 b5 0e 89 00 48 8b 44 24 08 4c 8d 78 f8 4c 8b 6b 10 48 b8
RSP: 0018:ffffc9000342ea08 EFLAGS: 00000246
RAX: 1ffff92000685d5b RBX: ffffc9000342eac8 RCX: ffffffff8d9eb390
RDX: 1ffffffff1c1b2c4 RSI: ffffffff8e0d9620 RDI: ffffc9000342ead8
RBP: ffffc9000342eb10 R08: 0000000000000006 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000685d65 R12: 1ffffffff1c1b2c4
R13: dffffc0000000000 R14: ffffc90003428000 R15: ffffffff8e0d9625
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3225 [inline]
slab_alloc mm/slub.c:3233 [inline]
kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
kmem_cache_zalloc include/linux/slab.h:728 [inline]
__kernfs_new_node+0xe3/0x6c0 fs/kernfs/dir.c:593
kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:669
__kernfs_create_file+0x47/0x2e0 fs/kernfs/file.c:985
sysfs_add_file_mode_ns+0x2d4/0x3a0 fs/sysfs/file.c:317
create_files fs/sysfs/group.c:64 [inline]
internal_create_group+0x495/0xd00 fs/sysfs/group.c:149
internal_create_groups fs/sysfs/group.c:189 [inline]
sysfs_create_groups+0x55/0x120 fs/sysfs/group.c:215
create_dir lib/kobject.c:100 [inline]
kobject_add_internal+0x82c/0xd90 lib/kobject.c:263
kobject_add_varg lib/kobject.c:398 [inline]
kobject_init_and_add+0x128/0x190 lib/kobject.c:481
netdev_queue_add_kobject net/core/net-sysfs.c:1666 [inline]
netdev_queue_update_kobjects+0x19c/0x3e0 net/core/net-sysfs.c:1711
register_queue_kobjects net/core/net-sysfs.c:1772 [inline]
netdev_register_kobject+0x273/0x320 net/core/net-sysfs.c:2018
register_netdevice+0x1039/0x16f0 net/core/dev.c:10397
__ip_tunnel_create+0x2c7/0x390 net/ipv4/ip_tunnel.c:267
ip_tunnel_init_net+0x246/0x6f0 net/ipv4/ip_tunnel.c:1084
vti_init_net+0x2b/0xf0 net/ipv4/ip_vti.c:504
ops_init+0x357/0x600 net/core/net_namespace.c:138
setup_net+0x39e/0xa10 net/core/net_namespace.c:333
copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178
copy_process+0x1834/0x3e20 kernel/fork.c:2293
kernel_clone+0x23f/0x990 kernel/fork.c:2679
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x19a/0x210 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f334eaa5cb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f334cd00fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f334ed20fa0 RCX: 00007f334eaa5cb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000640c7000
RBP: 00007f334eb13bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f334ed21038 R14: 00007f334ed20fa0 R15: 00007ffd6f27b548
----------------
Code disassembly (best guess):
0: f8 clc
1: 48 c1 e8 03 shr $0x3,%rax
5: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
a: 74 05 je 0x11
c: e8 d5 0e 89 00 call 0x890ee6
11: 4c 89 7c 24 60 mov %r15,0x60(%rsp)
16: 4c 8b 73 08 mov 0x8(%rbx),%r14
1a: 48 8d 7b 10 lea 0x10(%rbx),%rdi
1e: 48 89 f8 mov %rdi,%rax
21: 48 c1 e8 03 shr $0x3,%rax
25: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
* 2a: 74 05 je 0x31 <-- trapping instruction
2c: e8 b5 0e 89 00 call 0x890ee6
31: 48 8b 44 24 08 mov 0x8(%rsp),%rax
36: 4c 8d 78 f8 lea -0x8(%rax),%r15
3a: 4c 8b 6b 10 mov 0x10(%rbx),%r13
3e: 48 rex.W
3f: b8 .byte 0xb8