====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.672/7603 is trying to acquire lock: ffff8880b8e37de8 (stock_lock ){..-.}-{2:2} , at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] , at: consume_stock mm/memcontrol.c:2274 [inline] , at: try_charge_memcg+0x21a/0x17c0 mm/memcontrol.c:2684 but task is already holding lock: ffff8880789f3238 (&trie->lock ){-.-.}-{2:2} , at: trie_update_elem+0xc4/0xd60 kernel/bpf/lpm_trie.c:335 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ( &trie->lock){-.-.}-{2:2} : __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb4/0x100 kernel/locking/spinlock.c:162 trie_delete_elem+0x94/0x630 kernel/bpf/lpm_trie.c:466 0xffffffffa0000992 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:617 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_prog_run_array include/linux/bpf.h:1994 [inline] trace_call_bpf+0x333/0x6c0 kernel/trace/bpf_trace.c:143 perf_trace_run_bpf_submit+0x7a/0x1c0 kernel/events/core.c:10287 perf_trace_lock_acquire+0x342/0x400 include/trace/events/lock.h:24 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x3ef/0x420 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] mod_objcg_mlstate+0xad/0x320 mm/memcontrol.c:2913 mod_objcg_state+0x44b/0x8c0 mm/memcontrol.c:3254 memcg_slab_free_hook+0x167/0x200 mm/slab.h:577 slab_free mm/slub.c:3825 [inline] kmem_cache_free+0xe1/0x290 mm/slub.c:3852 rcu_do_batch kernel/rcu/tree.c:2194 [inline] rcu_core+0x9c1/0x17f0 kernel/rcu/tree.c:2467 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 run_ksoftirqd+0xa8/0x100 kernel/softirq.c:950 smpboot_thread_fn+0x651/0x9f0 kernel/smpboot.c:164 kthread+0x2fa/0x390 kernel/kthread.c:388 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 ( stock_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+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] consume_stock mm/memcontrol.c:2274 [inline] try_charge_memcg+0x237/0x17c0 mm/memcontrol.c:2684 obj_cgroup_charge_pages mm/memcontrol.c:3138 [inline] __memcg_kmem_charge_page+0x224/0x380 mm/memcontrol.c:3164 __alloc_pages+0x222/0x460 mm/page_alloc.c:4518 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] __kmalloc_large_node+0x8c/0x1f0 mm/slab_common.c:1148 __do_kmalloc_node mm/slab_common.c:995 [inline] __kmalloc_node+0x112/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] bpf_map_kmalloc_node+0xbc/0x1b0 kernel/bpf/syscall.c:424 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline] trie_update_elem+0x172/0xd60 kernel/bpf/lpm_trie.c:338 bpf_map_update_value+0x64b/0x710 kernel/bpf/syscall.c:203 map_update_elem+0x586/0x710 kernel/bpf/syscall.c:1567 __sys_bpf+0x6b5/0x890 kernel/bpf/syscall.c:5466 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&trie->lock ); lock( stock_lock); lock(&trie->lock ); lock( stock_lock); *** DEADLOCK *** 2 locks held by syz.2.672/7603: #0: ffffffff8d131da0 (rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] , at: rcu_read_lock include/linux/rcupdate.h:786 [inline] , at: bpf_map_update_value+0x408/0x710 kernel/bpf/syscall.c:202 #1: ffff8880789f3238 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xc4/0xd60 kernel/bpf/lpm_trie.c:335 stack backtrace: CPU: 0 PID: 7603 Comm: syz.2.672 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/0x400 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+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] consume_stock mm/memcontrol.c:2274 [inline] try_charge_memcg+0x237/0x17c0 mm/memcontrol.c:2684 obj_cgroup_charge_pages mm/memcontrol.c:3138 [inline] __memcg_kmem_charge_page+0x224/0x380 mm/memcontrol.c:3164 __alloc_pages+0x222/0x460 mm/page_alloc.c:4518 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] __kmalloc_large_node+0x8c/0x1f0 mm/slab_common.c:1148 __do_kmalloc_node mm/slab_common.c:995 [inline] __kmalloc_node+0x112/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] bpf_map_kmalloc_node+0xbc/0x1b0 kernel/bpf/syscall.c:424 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline] trie_update_elem+0x172/0xd60 kernel/bpf/lpm_trie.c:338 bpf_map_update_value+0x64b/0x710 kernel/bpf/syscall.c:203 map_update_elem+0x586/0x710 kernel/bpf/syscall.c:1567 __sys_bpf+0x6b5/0x890 kernel/bpf/syscall.c:5466 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f092459e0d9 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:00007f09227f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f0924825fa0 RCX: 00007f092459e0d9 RDX: 0000000000000020 RSI: 0000200000000080 RDI: 0000000000000002 RBP: 00007f0924635024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0924826038 R14: 00007f0924825fa0 R15: 00007ffd06636938 pim6reg0: tun_chr_ioctl cmd 1074025672 pim6reg0: ignored: set checksum disabled