================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. klogd/4972 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88807f6f8260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] ffff88807f6f8260 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1778 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5908 lock_sock_nested+0x41/0x100 net/core/sock.c:3827 lock_sock include/net/sock.h:1713 [inline] x25_bind+0x209/0x450 net/x25/af_x25.c:694 __sys_bind_socket net/socket.c:1945 [inline] __sys_bind+0x2e3/0x410 net/socket.c:1976 __do_sys_bind net/socket.c:1981 [inline] __se_sys_bind net/socket.c:1979 [inline] __x64_sys_bind+0x7a/0x90 net/socket.c:1979 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 306636 hardirqs last enabled at (306636): [] __local_bh_enable_ip+0xd6/0x140 kernel/softirq.c:478 hardirqs last disabled at (306635): [] __local_bh_enable_ip+0x72/0x140 kernel/softirq.c:455 softirqs last enabled at (306396): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last enabled at (306396): [] __alloc_skb+0x18d/0x7a0 net/core/skbuff.c:697 softirqs last disabled at (306417): [] __do_softirq kernel/softirq.c:679 [inline] softirqs last disabled at (306417): [] invoke_softirq kernel/softirq.c:519 [inline] softirqs last disabled at (306417): [] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** locks held by klogd/4972: 1, last CPU#0: #0: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6269 stack backtrace: CPU: 0 UID: 0 PID: 4972 Comm: klogd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_usage_bug+0x28c/0x2e0 kernel/locking/lockdep.c:4058 valid_state+0xbe/0xf0 kernel/locking/lockdep.c:4072 mark_lock_irq+0x36/0x380 kernel/locking/lockdep.c:4283 mark_lock+0x117/0x190 kernel/locking/lockdep.c:4769 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0x6b7/0x2e50 kernel/locking/lockdep.c:5208 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5908 lock_sock_nested+0x41/0x100 net/core/sock.c:3827 lock_sock include/net/sock.h:1713 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1778 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6245 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6270 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7768 napi_poll net/core/dev.c:7831 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7988 handle_softirqs+0x226/0x860 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:in_gate_area_no_mm+0x0/0x60 arch/x86/entry/vsyscall/vsyscall_64.c:351 Code: fb 41 0f 92 c6 44 89 f0 5b 41 5e 41 5f 5d e9 c7 96 ab 0a cc 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <0f> 1f 40 d6 55 53 48 89 fb e8 d2 46 94 00 8b 2d fc 6c 1e 0d bf 02 RSP: 0018:ffffc90002e97710 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007fe1c8cd7a37 RCX: 0000000000000001 RDX: ffffffff90e74800 RSI: ffffffff8e4dc9a1 RDI: 00007fe1c8cd7a37 RBP: 0000000000000001 R08: ffffc90002e97f48 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb5c8a0 R12: ffff88807f6cddc0 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920005d2ef6 is_kernel_text include/linux/kallsyms.h:31 [inline] core_kernel_text kernel/extable.c:68 [inline] kernel_text_address+0x2d/0xe0 kernel/extable.c:99 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 syslog_print+0x57c/0x610 kernel/printk/printk.c:1677 do_syslog+0x583/0x7d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe1c8cd7a37 Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007fffde618ee8 EFLAGS: 00000206 ORIG_RAX: 0000000000000067 RAX: ffffffffffffffda RBX: 00007fe1c8e77490 RCX: 00007fe1c8cd7a37 RDX: 00000000000003ff RSI: 00007fe1c8e77490 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000206 R12: 00007fe1c8e77490 R13: 00007fe1c8e54dfe R14: 00007fe1c8e774d8 R15: 00007fe1c8e774d8 BUG: sleeping function called from invalid context at net/core/sock.c:3829 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 4972, name: klogd preempt_count: 100, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:486 [inline] [] handle_softirqs+0xab/0x860 kernel/softirq.c:621 CPU: 0 UID: 0 PID: 4972 Comm: klogd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 __might_resched+0x36a/0x4c0 kernel/sched/core.c:9203 lock_sock_nested+0x56/0x100 net/core/sock.c:3829 lock_sock include/net/sock.h:1713 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1778 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6245 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6270 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7768 napi_poll net/core/dev.c:7831 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7988 handle_softirqs+0x226/0x860 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:in_gate_area_no_mm+0x0/0x60 arch/x86/entry/vsyscall/vsyscall_64.c:351 Code: fb 41 0f 92 c6 44 89 f0 5b 41 5e 41 5f 5d e9 c7 96 ab 0a cc 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <0f> 1f 40 d6 55 53 48 89 fb e8 d2 46 94 00 8b 2d fc 6c 1e 0d bf 02 RSP: 0018:ffffc90002e97710 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007fe1c8cd7a37 RCX: 0000000000000001 RDX: ffffffff90e74800 RSI: ffffffff8e4dc9a1 RDI: 00007fe1c8cd7a37 RBP: 0000000000000001 R08: ffffc90002e97f48 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb5c8a0 R12: ffff88807f6cddc0 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920005d2ef6 is_kernel_text include/linux/kallsyms.h:31 [inline] core_kernel_text kernel/extable.c:68 [inline] kernel_text_address+0x2d/0xe0 kernel/extable.c:99 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 syslog_print+0x57c/0x610 kernel/printk/printk.c:1677 do_syslog+0x583/0x7d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe1c8cd7a37 Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007fffde618ee8 EFLAGS: 00000206 ORIG_RAX: 0000000000000067 RAX: ffffffffffffffda RBX: 00007fe1c8e77490 RCX: 00007fe1c8cd7a37 RDX: 00000000000003ff RSI: 00007fe1c8e77490 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000206 R12: 00007fe1c8e77490 R13: 00007fe1c8e54dfe R14: 00007fe1c8e774d8 R15: 00007fe1c8e774d8 ---------------- Code disassembly (best guess): 0: fb sti 1: 41 0f 92 c6 setb %r14b 5: 44 89 f0 mov %r14d,%eax 8: 5b pop %rbx 9: 41 5e pop %r14 b: 41 5f pop %r15 d: 5d pop %rbp e: e9 c7 96 ab 0a jmp 0xaab96da 13: cc int3 14: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: 0f 1f 40 d6 nopl -0x2a(%rax) <-- trapping instruction 2e: 55 push %rbp 2f: 53 push %rbx 30: 48 89 fb mov %rdi,%rbx 33: e8 d2 46 94 00 call 0x94470a 38: 8b 2d fc 6c 1e 0d mov 0xd1e6cfc(%rip),%ebp # 0xd1e6d3a 3e: bf .byte 0xbf 3f: 02 .byte 0x2