===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.8.0-syzkaller-05236-g443574b03387 #0 Not tainted ----------------------------------------------------- syz-executor.1/6004 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: ffff888069427a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888069427a00 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:414 [inline] ffff888069427a00 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x97/0x140 net/core/sock_map.c:446 and this task is already holding: ffff88801ddb8018 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 which would create a new lock dependency: (&sighand->siglock){-.-.}-{2:2} -> (&stab->lock){+...}-{2:2} but this new dependency connects a HARDIRQ-irq-safe lock: (&sighand->siglock){-.-.}-{2:2} ... which became HARDIRQ-irq-safe at: lock_acquire+0x1e4/0x530 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_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe2/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xa8/0x3e0 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x156e/0x1850 kernel/signal.c:2910 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x270 kernel/entry/common.c:225 exc_general_protection+0x410/0x5d0 arch/x86/kernel/traps.c:644 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617 to a HARDIRQ-irq-unsafe lock: (&stab->lock){+...}-{2:2} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:490 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:579 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&stab->lock); local_irq_disable(); lock(&sighand->siglock); lock(&stab->lock); lock(&sighand->siglock); *** DEADLOCK *** 3 locks held by syz-executor.1/6004: #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420 #1: ffff88801ddb8018 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run5+0x197/0x4a0 kernel/trace/bpf_trace.c:2423 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&sighand->siglock){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x1e4/0x530 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_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe2/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xa8/0x3e0 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x156e/0x1850 kernel/signal.c:2910 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x270 kernel/entry/common.c:225 exc_general_protection+0x410/0x5d0 arch/x86/kernel/traps.c:644 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617 IN-SOFTIRQ-W at: lock_acquire+0x1e4/0x530 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_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_780926d3cf2d1f56+0x4c/0xa3 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_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_consume_skb+0x18a/0x1f0 include/trace/events/skb.h:54 consume_skb+0x73/0x160 net/core/skbuff.c:1431 dummy_xmit+0x12c/0x1b0 drivers/net/dummy.c:64 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547 __dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip6_finish_output2+0xfc0/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509 addrconf_rs_timer+0x36e/0x660 net/ipv6/addrconf.c:4037 call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2408 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419 run_timer_base kernel/time/timer.c:2428 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 lock_acquire+0x25b/0x530 kernel/locking/lockdep.c:5758 rcu_lock_acquire include/linux/rcupdate.h:298 [inline] rcu_read_lock include/linux/rcupdate.h:750 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:508 page_table_check_set+0x5d/0x700 mm/page_table_check.c:109 __page_table_check_ptes_set+0x220/0x280 mm/page_table_check.c:196 page_table_check_ptes_set include/linux/page_table_check.h:74 [inline] set_ptes include/linux/pgtable.h:241 [inline] copy_present_pte mm/memory.c:993 [inline] copy_pte_range mm/memory.c:1102 [inline] copy_pmd_range mm/memory.c:1187 [inline] copy_pud_range mm/memory.c:1224 [inline] copy_p4d_range mm/memory.c:1248 [inline] copy_page_range+0x2c7f/0x4240 mm/memory.c:1346 dup_mmap kernel/fork.c:747 [inline] dup_mm kernel/fork.c:1687 [inline] copy_mm+0x12f5/0x21b0 kernel/fork.c:1736 copy_process+0x187a/0x3df0 kernel/fork.c:2389 kernel_clone+0x21e/0x8d0 kernel/fork.c:2796 __do_sys_clone kernel/fork.c:2939 [inline] __se_sys_clone kernel/fork.c:2923 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2923 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] calculate_sigpending+0x4f/0x90 kernel/signal.c:188 ret_from_fork+0x24/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 } ... key at: [] sighand_ctor.__key+0x0/0x20 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&stab->lock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:490 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:579 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_map_update_common+0x1b6/0x5b0 net/core/sock_map.c:490 sock_map_update_elem_sys+0x55f/0x910 net/core/sock_map.c:579 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] sock_map_alloc.__key+0x0/0x20 ... acquired at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __sock_map_delete net/core/sock_map.c:414 [inline] sock_map_delete_elem+0x97/0x140 net/core/sock_map.c:446 bpf_prog_8a405b5ced52e191+0x4a/0x4e 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_run5+0x282/0x4a0 kernel/trace/bpf_trace.c:2423 trace_signal_generate+0x194/0x200 include/trace/events/signal.h:50 __send_signal_locked+0xb44/0xdc0 kernel/signal.c:1187 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_8cc4ff36b5985b6a+0x1d/0x1f 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_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work+0x153/0x170 kernel/entry/common.c:163 syscall_exit_to_user_mode_prepare kernel/entry/common.c:194 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x273/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 1 PID: 6004 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller-05236-g443574b03387 #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+0x1e7/0x2e0 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline] check_irq_usage kernel/locking/lockdep.c:2865 [inline] check_prev_add kernel/locking/lockdep.c:3138 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x4dc7/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __sock_map_delete net/core/sock_map.c:414 [inline] sock_map_delete_elem+0x97/0x140 net/core/sock_map.c:446 bpf_prog_8a405b5ced52e191+0x4a/0x4e 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_run5+0x282/0x4a0 kernel/trace/bpf_trace.c:2423 trace_signal_generate+0x194/0x200 include/trace/events/signal.h:50 __send_signal_locked+0xb44/0xdc0 kernel/signal.c:1187 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_8cc4ff36b5985b6a+0x1d/0x1f 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_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work+0x153/0x170 kernel/entry/common.c:163 syscall_exit_to_user_mode_prepare kernel/entry/common.c:194 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x273/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7fe04627dea9 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:00007fe0470530c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: 0000000000000010 RBX: 00007fe0463abf80 RCX: 00007fe04627dea9 RDX: 0000000000000010 RSI: 00000000200002c0 RDI: 0000000000000011 RBP: 00007fe0462ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe0463abf80 R15: 00007fff1a34f828