======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.672/8213 is trying to acquire lock:
ffff8880b8e29370 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2959 [inline]
ffff8880b8e29370 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3368 [inline]
ffff8880b8e29370 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3453
but task is already holding lock:
ffff8880b8e29598 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&base->lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
lock_timer_base+0x123/0x270 kernel/time/timer.c:999
__mod_timer+0xf9/0xdb0 kernel/time/timer.c:1080
queue_delayed_work_on+0x12a/0x1e0 kernel/workqueue.c:1987
kvfree_call_rcu+0x541/0x780 kernel/rcu/tree.c:3481
rtnl_register_internal+0x486/0x590 net/core/rtnetlink.c:264
rtnl_register+0x32/0x70 net/core/rtnetlink.c:314
ip_rt_init+0x2ec/0x390 net/ipv4/route.c:3796
ip_init+0xe/0x20 net/ipv4/ip_output.c:1663
inet_init+0x2c1/0x3e0 net/ipv4/af_inet.c:2024
do_one_initcall+0x1fd/0x750 init/main.c:1238
do_initcall_level+0x137/0x1f0 init/main.c:1300
do_initcalls+0x69/0xd0 init/main.c:1316
kernel_init_freeable+0x3d2/0x570 init/main.c:1553
kernel_init+0x1d/0x1c0 init/main.c:1443
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #0 (krc.lock){..-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2959 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3368 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3453
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_5186c38a4019a4cb+0x4a/0x4e
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:612 [inline]
bpf_prog_run include/linux/filter.h:619 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline]
bpf_trace_run3+0x1e7/0x400 kernel/trace/bpf_trace.c:2362
__bpf_trace_timer_start+0x14a/0x1b0 include/trace/events/timer.h:53
trace_timer_start include/trace/events/timer.h:53 [inline]
enqueue_timer+0x398/0x530 kernel/time/timer.c:609
internal_add_timer kernel/time/timer.c:634 [inline]
__mod_timer+0x977/0xdb0 kernel/time/timer.c:1131
mrp_join_timer_arm net/802/mrp.c:596 [inline]
mrp_join_timer+0x13f/0x170 net/802/mrp.c:611
call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x52d/0x7d0 kernel/time/timer.c:2022
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
__sanitizer_cov_trace_pc+0x0/0x60
__orc_find arch/x86/kernel/unwind_orc.c:99 [inline]
orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
unwind_next_frame+0x501/0x2970 arch/x86/kernel/unwind_orc.c:494
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__set_page_owner+0x1d/0x60 mm/page_owner.c:192
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1561 [inline]
get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
__alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
alloc_slab_page+0x5d/0x170 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2e0 mm/slub.c:2081
___slab_alloc+0xc6d/0x1300 mm/slub.c:3253
__slab_alloc mm/slub.c:3339 [inline]
__slab_alloc_node mm/slub.c:3392 [inline]
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc_node+0xa4/0x230 mm/slab_common.c:1014
kmalloc_node include/linux/slab.h:620 [inline]
kvmalloc_node+0x70/0x180 mm/util.c:617
kvmalloc include/linux/slab.h:738 [inline]
kvmalloc_array include/linux/slab.h:756 [inline]
__ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline]
ptr_ring_init include/linux/ptr_ring.h:489 [inline]
skb_array_init include/linux/skb_array.h:182 [inline]
pfifo_fast_init+0x238/0x6a0 net/sched/sch_generic.c:867
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016
mq_init+0x2e3/0x660 net/sched/sch_mq.c:90
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016
attach_default_qdiscs net/sched/sch_generic.c:1196 [inline]
dev_activate+0x1d0/0x11a0 net/sched/sch_generic.c:1250
__dev_open+0x338/0x430 net/core/dev.c:1515
__dev_change_flags+0x20e/0x6a0 net/core/dev.c:8685
dev_change_flags+0x88/0x1a0 net/core/dev.c:8757
dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529
dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786
sock_do_ioctl+0x226/0x2f0 net/socket.c:1236
sock_ioctl+0x623/0x7a0 net/socket.c:1341
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&base->lock);
lock(krc.lock);
lock(&base->lock);
lock(krc.lock);
*** DEADLOCK ***
5 locks held by syz.0.672/8213:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x7d2/0x1170 net/core/dev_ioctl.c:785
#1: ffffc90000007c00 ((&app->join_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbf/0x530 kernel/time/timer.c:1697
#2: ffff88814c71e4c8 (&app->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88814c71e4c8 (&app->lock){+.-.}-{2:2}, at: mrp_join_timer+0xd8/0x170 net/802/mrp.c:609
#3: ffff8880b8e29598 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline]
#4: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0xf4/0x400 kernel/trace/bpf_trace.c:2362
stack backtrace:
CPU: 0 PID: 8213 Comm: syz.0.672 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2959 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3368 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3453
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_5186c38a4019a4cb+0x4a/0x4e
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:612 [inline]
bpf_prog_run include/linux/filter.h:619 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline]
bpf_trace_run3+0x1e7/0x400 kernel/trace/bpf_trace.c:2362
__bpf_trace_timer_start+0x14a/0x1b0 include/trace/events/timer.h:53
trace_timer_start include/trace/events/timer.h:53 [inline]
enqueue_timer+0x398/0x530 kernel/time/timer.c:609
internal_add_timer kernel/time/timer.c:634 [inline]
__mod_timer+0x977/0xdb0 kernel/time/timer.c:1131
mrp_join_timer_arm net/802/mrp.c:596 [inline]
mrp_join_timer+0x13f/0x170 net/802/mrp.c:611
call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x52d/0x7d0 kernel/time/timer.c:2022
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212
Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d cc fc c4 0c 48 89 de 5b e9 53 88 56 00 cc cc cc 0f 1e fa 48 8b 04 24 65 48 8b 0d e0 2c 7e 7e 65 8b 15 e1 2c 7e
RSP: 0018:ffffc900038d6f10 EFLAGS: 00000202
RAX: ffffffff8e61bbf0 RBX: ffffffff8e61bbf4 RCX: ffff88807a28da00
RDX: 0000000000000002 RSI: ffffffff81d125db RDI: ffffffff81d10c91
RBP: ffffffff8e61bbf4 R08: ffffc900038d70b0 R09: 0000000000000001
R10: 0000000000000004 R11: 0000000000000002 R12: ffffffff8e61bbf8
R13: ffffffff81d10c91 R14: ffffffff81d125db R15: ffffffff8e61bbf4
__orc_find arch/x86/kernel/unwind_orc.c:99 [inline]
orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
unwind_next_frame+0x501/0x2970 arch/x86/kernel/unwind_orc.c:494
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__set_page_owner+0x1d/0x60 mm/page_owner.c:192
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1561 [inline]
get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
__alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
alloc_slab_page+0x5d/0x170 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2e0 mm/slub.c:2081
___slab_alloc+0xc6d/0x1300 mm/slub.c:3253
__slab_alloc mm/slub.c:3339 [inline]
__slab_alloc_node mm/slub.c:3392 [inline]
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc_node+0xa4/0x230 mm/slab_common.c:1014
kmalloc_node include/linux/slab.h:620 [inline]
kvmalloc_node+0x70/0x180 mm/util.c:617
kvmalloc include/linux/slab.h:738 [inline]
kvmalloc_array include/linux/slab.h:756 [inline]
__ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline]
ptr_ring_init include/linux/ptr_ring.h:489 [inline]
skb_array_init include/linux/skb_array.h:182 [inline]
pfifo_fast_init+0x238/0x6a0 net/sched/sch_generic.c:867
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016
mq_init+0x2e3/0x660 net/sched/sch_mq.c:90
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1016
attach_default_qdiscs net/sched/sch_generic.c:1196 [inline]
dev_activate+0x1d0/0x11a0 net/sched/sch_generic.c:1250
__dev_open+0x338/0x430 net/core/dev.c:1515
__dev_change_flags+0x20e/0x6a0 net/core/dev.c:8685
dev_change_flags+0x88/0x1a0 net/core/dev.c:8757
dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529
dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786
sock_do_ioctl+0x226/0x2f0 net/socket.c:1236
sock_ioctl+0x623/0x7a0 net/socket.c:1341
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5617f8eec9
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:00007f5618de1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f56181e5fa0 RCX: 00007f5617f8eec9
RDX: 0000200000002280 RSI: 0000000000008914 RDI: 0000000000000007
RBP: 00007f5618011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56181e6038 R14: 00007f56181e5fa0 R15: 00007fff24663368
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 0f 0b ud2
2: 0f 1f 80 00 00 00 00 nopl 0x0(%rax)
9: f3 0f 1e fa endbr64
d: 53 push %rbx
e: 48 89 fb mov %rdi,%rbx
11: e8 13 00 00 00 call 0x29
16: 48 8b 3d cc fc c4 0c mov 0xcc4fccc(%rip),%rdi # 0xcc4fce9
1d: 48 89 de mov %rbx,%rsi
20: 5b pop %rbx
21: e9 53 88 56 00 jmp 0x568879
26: cc int3
27: cc int3
28: cc int3
* 29: f3 0f 1e fa endbr64 <-- trapping instruction
2d: 48 8b 04 24 mov (%rsp),%rax
31: 65 48 8b 0d e0 2c 7e mov %gs:0x7e7e2ce0(%rip),%rcx # 0x7e7e2d19
38: 7e
39: 65 gs
3a: 8b .byte 0x8b
3b: 15 .byte 0x15
3c: e1 2c loope 0x6a
3e: 7e .byte 0x7e