====================================================== WARNING: possible circular locking dependency detected 6.1.143-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:19/4457 is trying to acquire lock: ffff8880284ada38 (&trie->lock){..-.}-{2:2}, at: trie_delete_elem+0x90/0x690 kernel/bpf/lpm_trie.c:467 but task is already holding lock: ffffffff96ea6338 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] ffffffff96ea6338 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&obj_hash[i].lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 slab_free_hook mm/slub.c:1699 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 trie_update_elem+0x6c1/0xe90 kernel/bpf/lpm_trie.c:444 bpf_map_update_value+0x5a0/0x670 kernel/bpf/syscall.c:226 generic_map_update_batch+0x569/0x850 kernel/bpf/syscall.c:1702 bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1 __sys_bpf+0x65f/0x6d0 kernel/bpf/syscall.c:-1 __do_sys_bpf kernel/bpf/syscall.c:5124 [inline] __se_sys_bpf kernel/bpf/syscall.c:5122 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5122 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&trie->lock){..-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 trie_delete_elem+0x90/0x690 kernel/bpf/lpm_trie.c:467 bpf_prog_1db1603a7cfa36fb+0x3d/0x41 bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324 trace_contention_end+0x13f/0x190 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0x7e8/0x9c0 kernel/locking/qspinlock.c:560 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x217/0x280 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xb0/0xf0 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 slab_free_hook mm/slub.c:1699 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5db/0x7c0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] kfree_skb_reason+0x163/0x370 net/core/skbuff.c:893 kfree_skb include/linux/skbuff.h:1220 [inline] ieee80211_iface_work+0x7b3/0xc80 net/mac80211/iface.c:1727 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&obj_hash[i].lock); lock(&trie->lock); lock(&obj_hash[i].lock); lock(&trie->lock); *** DEADLOCK *** 4 locks held by kworker/u4:19/4457: #0: ffff888020271938 ((wq_completion)phy17){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90004a3fd00 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff96ea6338 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] #2: ffffffff96ea6338 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 #3: ffffffff8cb2aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8cb2aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #3: ffffffff8cb2aaa0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] #3: ffffffff8cb2aaa0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xda/0x3b0 kernel/trace/bpf_trace.c:2324 stack backtrace: CPU: 1 PID: 4457 Comm: kworker/u4:19 Not tainted 6.1.143-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: phy17 ieee80211_iface_work Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 trie_delete_elem+0x90/0x690 kernel/bpf/lpm_trie.c:467 bpf_prog_1db1603a7cfa36fb+0x3d/0x41 bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324 trace_contention_end+0x13f/0x190 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0x7e8/0x9c0 kernel/locking/qspinlock.c:560 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x217/0x280 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xb0/0xf0 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 slab_free_hook mm/slub.c:1699 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5db/0x7c0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] kfree_skb_reason+0x163/0x370 net/core/skbuff.c:893 kfree_skb include/linux/skbuff.h:1220 [inline] ieee80211_iface_work+0x7b3/0xc80 net/mac80211/iface.c:1727 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295