================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.5.20959/31807 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88804ab70260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] ffff88804ab70260 (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_release+0xa0/0x3d0 net/x25/af_x25.c:632 __sock_release+0xa0/0x1f0 net/socket.c:735 sock_close+0x1c/0x30 net/socket.c:1526 __fput+0x418/0xa50 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x1fa/0x750 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline] do_syscall_64+0x328/0x510 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 4990 hardirqs last enabled at (4990): [] __local_bh_enable_ip+0xd0/0x130 kernel/softirq.c:457 hardirqs last disabled at (4989): [] __local_bh_enable_ip+0x71/0x130 kernel/softirq.c:434 softirqs last enabled at (4832): [] __do_softirq kernel/softirq.c:658 [inline] softirqs last enabled at (4832): [] invoke_softirq kernel/softirq.c:498 [inline] softirqs last enabled at (4832): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:737 softirqs last disabled at (4867): [] __do_softirq kernel/softirq.c:658 [inline] softirqs last disabled at (4867): [] invoke_softirq kernel/softirq.c:498 [inline] softirqs last disabled at (4867): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:737 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 syz.5.20959/31807: 1, last CPU#1: #0: ffffffff8eb5c820 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8eb5c820 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb5c820 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6269 stack backtrace: CPU: 1 UID: 0 PID: 31807 Comm: syz.5.20959 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+0x28b/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+0x225/0x840 kernel/softirq.c:624 __do_softirq kernel/softirq.c:658 [inline] invoke_softirq kernel/softirq.c:498 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:737 irq_exit_rcu+0x9/0x30 kernel/softirq.c:754 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:preempt_count_sub+0x1b/0x170 kernel/sched/core.c:6006 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 48 bb 00 00 00 00 00 fc ff df 48 c7 c0 80 75 7a 9a 48 c1 e8 03 <0f> b6 04 18 84 c0 0f 85 c5 00 00 00 83 3d 82 ad e5 18 00 75 25 65 RSP: 0018:ffffc90005ce77d0 EFLAGS: 00000a02 RAX: 1ffffffff34f4eb0 RBX: dffffc0000000000 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8c4c8960 RDI: 0000000000000001 RBP: 1ffff110096997d3 R08: ffffffff9058fd7f R09: 1ffffffff20b1faf R10: dffffc0000000000 R11: fffffbfff20b1fb0 R12: ffff88804b4cbeac R13: dffffc0000000000 R14: 1ffff110096997d0 R15: ffff88804b4cd1c8 __schedule_loop kernel/sched/core.c:7310 [inline] schedule+0x16e/0x2b0 kernel/sched/core.c:7324 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 rdmsrq_safe_on_cpu+0x18c/0x240 arch/x86/lib/msr-smp.c:165 msr_read+0x13a/0x230 arch/x86/kernel/msr.c:69 vfs_read+0x213/0xa80 fs/read_write.c:572 ksys_read+0x150/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb41539e0d9 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:00007fb4162d2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fb415625fa0 RCX: 00007fb41539e0d9 RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000003 RBP: 00007fb415435024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb415626038 R14: 00007fb415625fa0 R15: 00007ffcfab85808 BUG: sleeping function called from invalid context at net/core/sock.c:3829 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 31807, name: syz.5.20959 preempt_count: 101, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] __schedule_loop kernel/sched/core.c:7308 [inline] [] schedule+0x15d/0x2b0 kernel/sched/core.c:7324 CPU: 1 UID: 0 PID: 31807 Comm: syz.5.20959 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+0x378/0x4d0 kernel/sched/core.c:9195 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+0x225/0x840 kernel/softirq.c:624 __do_softirq kernel/softirq.c:658 [inline] invoke_softirq kernel/softirq.c:498 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:737 irq_exit_rcu+0x9/0x30 kernel/softirq.c:754 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:preempt_count_sub+0x1b/0x170 kernel/sched/core.c:6006 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 48 bb 00 00 00 00 00 fc ff df 48 c7 c0 80 75 7a 9a 48 c1 e8 03 <0f> b6 04 18 84 c0 0f 85 c5 00 00 00 83 3d 82 ad e5 18 00 75 25 65 RSP: 0018:ffffc90005ce77d0 EFLAGS: 00000a02 RAX: 1ffffffff34f4eb0 RBX: dffffc0000000000 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8c4c8960 RDI: 0000000000000001 RBP: 1ffff110096997d3 R08: ffffffff9058fd7f R09: 1ffffffff20b1faf R10: dffffc0000000000 R11: fffffbfff20b1fb0 R12: ffff88804b4cbeac R13: dffffc0000000000 R14: 1ffff110096997d0 R15: ffff88804b4cd1c8 __schedule_loop kernel/sched/core.c:7310 [inline] schedule+0x16e/0x2b0 kernel/sched/core.c:7324 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 rdmsrq_safe_on_cpu+0x18c/0x240 arch/x86/lib/msr-smp.c:165 msr_read+0x13a/0x230 arch/x86/kernel/msr.c:69 vfs_read+0x213/0xa80 fs/read_write.c:572 ksys_read+0x150/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb41539e0d9 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:00007fb4162d2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fb415625fa0 RCX: 00007fb41539e0d9 RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000003 RBP: 00007fb415435024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb415626038 R14: 00007fb415625fa0 R15: 00007ffcfab85808 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: f3 0f 1e fa endbr64 13: 55 push %rbp 14: 53 push %rbx 15: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 1c: fc ff df 1f: 48 c7 c0 80 75 7a 9a mov $0xffffffff9a7a7580,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 0f b6 04 18 movzbl (%rax,%rbx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 c5 00 00 00 jne 0xfb 36: 83 3d 82 ad e5 18 00 cmpl $0x0,0x18e5ad82(%rip) # 0x18e5adbf 3d: 75 25 jne 0x64 3f: 65 gs