================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.4.269/5357 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff888074852120 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1744 [inline] ffff888074852120 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5625 lock_sock_nested+0x44/0x100 net/core/sock.c:3258 lock_sock include/net/sock.h:1744 [inline] x25_bind+0x18a/0x3b0 net/x25/af_x25.c:698 __sys_bind+0x2e9/0x3e0 net/socket.c:1730 __do_sys_bind net/socket.c:1741 [inline] __se_sys_bind net/socket.c:1739 [inline] __x64_sys_bind+0x76/0x80 net/socket.c:1739 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 irq event stamp: 3494 hardirqs last enabled at (3494): [] __local_bh_enable_ip+0x136/0x1c0 kernel/softirq.c:406 hardirqs last disabled at (3493): [] __local_bh_enable_ip+0xd7/0x1c0 kernel/softirq.c:383 softirqs last enabled at (3198): [] local_bh_enable+0x5/0x20 include/linux/bottom_half.h:31 softirqs last disabled at (3447): [] __do_softirq kernel/softirq.c:610 [inline] softirqs last disabled at (3447): [] invoke_softirq kernel/softirq.c:450 [inline] softirqs last disabled at (3447): [] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** 1 lock held by syz.4.269/5357: #0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313 stack backtrace: CPU: 0 PID: 5357 Comm: syz.4.269 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:3932 mark_lock_irq+0xa9/0x900 kernel/locking/lockdep.c:4135 mark_lock+0x208/0x320 kernel/locking/lockdep.c:4591 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0xc63/0x7b50 kernel/locking/lockdep.c:4966 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5625 lock_sock_nested+0x44/0x100 net/core/sock.c:3258 lock_sock include/net/sock.h:1744 [inline] x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 x25_lapb_receive_frame+0x19d/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5551 [inline] netif_receive_skb_core+0x149/0x210 net/core/dev.c:5576 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x430 net/core/dev.c:7101 napi_poll net/core/dev.c:7168 [inline] net_rx_action+0x522/0xa80 net/core/dev.c:7258 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:40 [inline] RIP: 0010:__fpu_restore_sig arch/x86/kernel/fpu/signal.c:317 [inline] RIP: 0010:fpu__restore_sig+0x897/0x10a0 arch/x86/kernel/fpu/signal.c:466 Code: c7 44 27 0c f8 f8 f8 f8 66 43 c7 44 27 10 f8 f8 31 c0 e9 60 fa ff ff 44 8b ac 24 14 01 00 00 44 89 f7 44 89 ee e8 39 c5 4c 00 <45> 39 ee 76 0a e8 cf c3 4c 00 e9 e1 fa ff ff 4c 03 74 24 38 4c 89 RSP: 0018:ffffc900038c7b20 EFLAGS: 00000293 RAX: ffffffff812c50c7 RBX: 0000000000000000 RCX: ffff888029febb80 RDX: 0000000000000000 RSI: 0000000000000344 RDI: 0000000000000340 RBP: ffffc900038c7cd0 R08: 0000000000000000 R09: 1ffff92000718f8b R10: dffffc0000000000 R11: fffff52000718f8c R12: dffffc0000000000 R13: 0000000000000344 R14: 0000000000000340 R15: 1ffff92000718f70 restore_sigcontext arch/x86/kernel/signal.c:139 [inline] __ia32_sys_rt_sigreturn+0x5ef/0x750 arch/x86/kernel/signal.c:674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4de70c1159 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:00007fff44b44338 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00007f4de70c1159 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f4de7348fa8 RBP: 000000000000112e R08: 0000000000000000 R09: 0000000000000000 R10: 00007f4de7348fa0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4de7348fac R14: 00007f4de7348fa8 R15: 00007f4de7348fa0 BUG: sleeping function called from invalid context at net/core/sock.c:3260 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5357, name: syz.4.269 INFO: lockdep is turned off. Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:414 [inline] [] handle_softirqs+0xfd/0x830 kernel/softirq.c:552 CPU: 0 PID: 5357 Comm: syz.4.269 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 ___might_sleep+0x493/0x610 kernel/sched/core.c:9658 lock_sock_nested+0x5b/0x100 net/core/sock.c:3260 lock_sock include/net/sock.h:1744 [inline] x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 x25_lapb_receive_frame+0x19d/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5551 [inline] netif_receive_skb_core+0x149/0x210 net/core/dev.c:5576 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x430 net/core/dev.c:7101 napi_poll net/core/dev.c:7168 [inline] net_rx_action+0x522/0xa80 net/core/dev.c:7258 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:40 [inline] RIP: 0010:__fpu_restore_sig arch/x86/kernel/fpu/signal.c:317 [inline] RIP: 0010:fpu__restore_sig+0x897/0x10a0 arch/x86/kernel/fpu/signal.c:466 Code: c7 44 27 0c f8 f8 f8 f8 66 43 c7 44 27 10 f8 f8 31 c0 e9 60 fa ff ff 44 8b ac 24 14 01 00 00 44 89 f7 44 89 ee e8 39 c5 4c 00 <45> 39 ee 76 0a e8 cf c3 4c 00 e9 e1 fa ff ff 4c 03 74 24 38 4c 89 RSP: 0018:ffffc900038c7b20 EFLAGS: 00000293 RAX: ffffffff812c50c7 RBX: 0000000000000000 RCX: ffff888029febb80 RDX: 0000000000000000 RSI: 0000000000000344 RDI: 0000000000000340 RBP: ffffc900038c7cd0 R08: 0000000000000000 R09: 1ffff92000718f8b R10: dffffc0000000000 R11: fffff52000718f8c R12: dffffc0000000000 R13: 0000000000000344 R14: 0000000000000340 R15: 1ffff92000718f70 restore_sigcontext arch/x86/kernel/signal.c:139 [inline] __ia32_sys_rt_sigreturn+0x5ef/0x750 arch/x86/kernel/signal.c:674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4de70c1159 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:00007fff44b44338 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00007f4de70c1159 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f4de7348fa8 RBP: 000000000000112e R08: 0000000000000000 R09: 0000000000000000 R10: 00007f4de7348fa0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4de7348fac R14: 00007f4de7348fa8 R15: 00007f4de7348fa0 ---------------- Code disassembly (best guess): 0: c7 44 27 0c f8 f8 f8 movl $0xf8f8f8f8,0xc(%rdi,%riz,1) 7: f8 8: 66 43 c7 44 27 10 f8 movw $0xf8f8,0x10(%r15,%r12,1) f: f8 10: 31 c0 xor %eax,%eax 12: e9 60 fa ff ff jmp 0xfffffa77 17: 44 8b ac 24 14 01 00 mov 0x114(%rsp),%r13d 1e: 00 1f: 44 89 f7 mov %r14d,%edi 22: 44 89 ee mov %r13d,%esi 25: e8 39 c5 4c 00 call 0x4cc563 * 2a: 45 39 ee cmp %r13d,%r14d <-- trapping instruction 2d: 76 0a jbe 0x39 2f: e8 cf c3 4c 00 call 0x4cc403 34: e9 e1 fa ff ff jmp 0xfffffb1a 39: 4c 03 74 24 38 add 0x38(%rsp),%r14 3e: 4c rex.WR 3f: 89 .byte 0x89