======================================================
WARNING: possible circular locking dependency detected
6.6.93-syzkaller #0 Not tainted
------------------------------------------------------
syz.1.11/5859 is trying to acquire lock:
ffff8880b8e295a8 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2951 [inline]
ffff8880b8e295a8 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3360 [inline]
ffff8880b8e295a8 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3445
but task is already holding lock:
ffff8880b8e297d8 (&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:3473
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:3789
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:2951 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3360 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3445
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_2c29ac5cdc6b1842+0x42/0x46
bpf_dispatcher_nop_func include/linux/bpf.h:1213 [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
sk_reset_timer+0x23/0xc0 net/core/sock.c:3395
tipc_sk_finish_conn+0x154/0x7e0 net/tipc/socket.c:1676
tipc_socketpair+0x254/0x470 net/tipc/socket.c:3353
__sys_socketpair+0x2b0/0x550 net/socket.c:1795
__do_sys_socketpair net/socket.c:1831 [inline]
__se_sys_socketpair net/socket.c:1828 [inline]
__x64_sys_socketpair+0x9b/0xb0 net/socket.c:1828
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 ***
2 locks held by syz.1.11/5859:
#0: ffff8880b8e297d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline]
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0xf4/0x400 kernel/trace/bpf_trace.c:2362
stack backtrace:
CPU: 0 PID: 5859 Comm: syz.1.11 Not tainted 6.6.93-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
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:2951 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3360 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3445
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_2c29ac5cdc6b1842+0x42/0x46
bpf_dispatcher_nop_func include/linux/bpf.h:1213 [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
sk_reset_timer+0x23/0xc0 net/core/sock.c:3395
tipc_sk_finish_conn+0x154/0x7e0 net/tipc/socket.c:1676
tipc_socketpair+0x254/0x470 net/tipc/socket.c:3353
__sys_socketpair+0x2b0/0x550 net/socket.c:1795
__do_sys_socketpair net/socket.c:1831 [inline]
__se_sys_socketpair net/socket.c:1828 [inline]
__x64_sys_socketpair+0x9b/0xb0 net/socket.c:1828
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: 0033:0x7fad6358e929
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:00007fad6447c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007fad637b5fa0 RCX: 00007fad6358e929
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 000000000000001e
RBP: 00007fad63610b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000180 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fad637b5fa0 R15: 00007ffd9945ed68
</TASK>