====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc6-syzkaller-00132-g9adcac650618 #0 Not tainted ------------------------------------------------------ syz-executor.3/5889 is trying to acquire lock: ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2960 [inline] ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 but task is already holding lock: ffff88807e9f09f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&trie->lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 trie_delete_elem+0x96/0x6a0 kernel/bpf/lpm_trie.c:451 0xffffffffa0001ff1 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run4+0x25a/0x490 kernel/trace/bpf_trace.c:2422 trace_mm_page_alloc include/trace/events/kmem.h:177 [inline] __alloc_pages+0x694/0x6c0 mm/page_alloc.c:4597 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc+0x252/0x340 mm/slub.c:3852 kmem_cache_zalloc include/linux/slab.h:739 [inline] fill_pool lib/debugobjects.c:168 [inline] debug_objects_fill_pool+0x570/0x9b0 lib/debugobjects.c:615 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x30/0x3c0 kernel/time/hrtimer.c:1090 __run_hrtimer kernel/time/hrtimer.c:1709 [inline] __hrtimer_run_queues+0x6d5/0xd50 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 preempt_count arch/x86/include/asm/preempt.h:26 [inline] __local_bh_disable_ip+0x163/0x220 kernel/softirq.c:325 local_bh_disable include/linux/bottom_half.h:20 [inline] fpregs_lock arch/x86/include/asm/fpu/api.h:72 [inline] fpu__clear_user_states+0x49/0x270 arch/x86/kernel/fpu/core.c:745 handle_signal arch/x86/kernel/signal.c:283 [inline] arch_do_signal_or_restart+0x4fb/0x860 arch/x86/kernel/signal.c:312 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 exc_page_fault+0x585/0x8e0 arch/x86/mm/fault.c:1566 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (hrtimer_bases.lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1303 hrtimer_start include/linux/hrtimer.h:275 [inline] run_page_cache_worker kernel/rcu/tree.c:3341 [inline] kvfree_call_rcu+0x5e6/0x790 kernel/rcu/tree.c:3446 rtnl_register_internal+0x482/0x590 net/core/rtnetlink.c:265 rtnl_register+0x36/0x80 net/core/rtnetlink.c:315 ip_rt_init+0x2f5/0x3a0 net/ipv4/route.c:3720 ip_init+0xe/0x20 net/ipv4/ip_output.c:1663 inet_init+0x3d8/0x580 net/ipv4/af_inet.c:2023 do_one_initcall+0x248/0x880 init/main.c:1245 do_initcall_level+0x157/0x210 init/main.c:1307 do_initcalls+0x3f/0x80 init/main.c:1323 kernel_init_freeable+0x435/0x5d0 init/main.c:1555 kernel_init+0x1d/0x2b0 init/main.c:1444 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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:2960 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 trie_update_elem+0x819/0xc10 kernel/bpf/lpm_trie.c:385 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203 generic_map_update_batch+0x60d/0x900 kernel/bpf/syscall.c:1876 bpf_map_do_batch+0x3e0/0x690 kernel/bpf/syscall.c:5174 __sys_bpf+0x377/0x810 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: krc.lock --> hrtimer_bases.lock --> &trie->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&trie->lock); lock(hrtimer_bases.lock); lock(&trie->lock); lock(krc.lock); *** DEADLOCK *** 2 locks held by syz-executor.3/5889: #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x3c4/0x540 kernel/bpf/syscall.c:202 #1: ffff88807e9f09f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324 stack backtrace: CPU: 1 PID: 5889 Comm: syz-executor.3 Not tainted 6.9.0-rc6-syzkaller-00132-g9adcac650618 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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:2960 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 trie_update_elem+0x819/0xc10 kernel/bpf/lpm_trie.c:385 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203 generic_map_update_batch+0x60d/0x900 kernel/bpf/syscall.c:1876 bpf_map_do_batch+0x3e0/0x690 kernel/bpf/syscall.c:5174 __sys_bpf+0x377/0x810 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0a4aa7dca9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0a4b83f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f0a4ababf80 RCX: 00007f0a4aa7dca9 RDX: 0000000000000038 RSI: 0000000020000680 RDI: 000000000000001a RBP: 00007f0a4aac947e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f0a4ababf80 R15: 00007ffe7cdef038