================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.4.191/6564 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff888032b60260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] ffff888032b60260 (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+0x166/0x510 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 53098 hardirqs last enabled at (53098): [] __local_bh_enable_ip+0xd0/0x130 kernel/softirq.c:455 hardirqs last disabled at (53097): [] __local_bh_enable_ip+0x71/0x130 kernel/softirq.c:432 softirqs last enabled at (52004): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (52004): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (52004): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 softirqs last disabled at (52921): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (52921): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (52921): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 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.4.191/6564: 2, last CPU#0: #0: ffff888025f629f8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff888025f629f8 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x182/0x390 mm/gup.c:1942 #1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6265 stack backtrace: CPU: 0 UID: 0 PID: 6564 Comm: syz.4.191 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:6241 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6266 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7764 napi_poll net/core/dev.c:7827 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7984 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 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+0x65/0x170 kernel/sched/core.c:6018 Code: ff ff ff 7f 39 cf 7f 2a 81 ff ff 00 00 00 0f 93 c1 84 c0 0f 95 c0 08 c8 74 58 65 8b 05 b4 83 dc 11 f7 df 65 01 3d ab 83 dc 11 <5b> 5d e9 14 7b 49 0a cc 90 e8 dd 5f 40 03 85 c0 74 33 48 c7 c0 84 RSP: 0018:ffffc9000d5bf338 EFLAGS: 00000297 RAX: 0000000080000001 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000007 RSI: ffffffff8e253559 RDI: 00000000ffffffff RBP: ffffc9000d5bf4b0 R08: ffffffff9058fb7f R09: 1ffffffff20b1f6f R10: dffffc0000000000 R11: fffffbfff20b1f70 R12: dffffc0000000000 R13: ffffc9000d5bf400 R14: 0000000000000000 R15: 0000000000000001 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] _raw_spin_unlock_irq+0x2e/0x50 kernel/locking/spinlock.c:206 spin_unlock_irq include/linux/spinlock.h:402 [inline] shmem_add_to_page_cache+0xa5e/0xd40 mm/shmem.c:938 shmem_alloc_and_add_folio+0x854/0xf60 mm/shmem.c:2000 shmem_get_folio_gfp+0x5da/0x16d0 mm/shmem.c:2527 shmem_fault+0x179/0x390 mm/shmem.c:2728 __do_fault+0x138/0x2a0 mm/memory.c:5566 do_read_fault mm/memory.c:6001 [inline] do_fault mm/memory.c:6135 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6559 [inline] __handle_mm_fault mm/memory.c:6708 [inline] handle_mm_fault+0x1a53/0x3750 mm/memory.c:6877 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1675/0x2750 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4230 [inline] vm_mmap_pgoff+0x353/0x4e0 mm/util.c:586 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: 0033:0x7f32c779e0d9 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:00007f32c8708028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f32c7a25fa0 RCX: 00007f32c779e0d9 RDX: b635773f06ebbeeb RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f32c7835024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f32c7a26038 R14: 00007f32c7a25fa0 R15: 00007ffe4acf6648 BUG: sleeping function called from invalid context at net/core/sock.c:3829 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6564, name: syz.4.191 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:463 [inline] [] handle_softirqs+0xab/0x840 kernel/softirq.c:598 CPU: 0 UID: 0 PID: 6564 Comm: syz.4.191 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:6241 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6266 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7764 napi_poll net/core/dev.c:7827 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7984 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 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+0x65/0x170 kernel/sched/core.c:6018 Code: ff ff ff 7f 39 cf 7f 2a 81 ff ff 00 00 00 0f 93 c1 84 c0 0f 95 c0 08 c8 74 58 65 8b 05 b4 83 dc 11 f7 df 65 01 3d ab 83 dc 11 <5b> 5d e9 14 7b 49 0a cc 90 e8 dd 5f 40 03 85 c0 74 33 48 c7 c0 84 RSP: 0018:ffffc9000d5bf338 EFLAGS: 00000297 RAX: 0000000080000001 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000007 RSI: ffffffff8e253559 RDI: 00000000ffffffff RBP: ffffc9000d5bf4b0 R08: ffffffff9058fb7f R09: 1ffffffff20b1f6f R10: dffffc0000000000 R11: fffffbfff20b1f70 R12: dffffc0000000000 R13: ffffc9000d5bf400 R14: 0000000000000000 R15: 0000000000000001 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] _raw_spin_unlock_irq+0x2e/0x50 kernel/locking/spinlock.c:206 spin_unlock_irq include/linux/spinlock.h:402 [inline] shmem_add_to_page_cache+0xa5e/0xd40 mm/shmem.c:938 shmem_alloc_and_add_folio+0x854/0xf60 mm/shmem.c:2000 shmem_get_folio_gfp+0x5da/0x16d0 mm/shmem.c:2527 shmem_fault+0x179/0x390 mm/shmem.c:2728 __do_fault+0x138/0x2a0 mm/memory.c:5566 do_read_fault mm/memory.c:6001 [inline] do_fault mm/memory.c:6135 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6559 [inline] __handle_mm_fault mm/memory.c:6708 [inline] handle_mm_fault+0x1a53/0x3750 mm/memory.c:6877 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1675/0x2750 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4230 [inline] vm_mmap_pgoff+0x353/0x4e0 mm/util.c:586 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: 0033:0x7f32c779e0d9 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:00007f32c8708028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f32c7a25fa0 RCX: 00007f32c779e0d9 RDX: b635773f06ebbeeb RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f32c7835024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f32c7a26038 R14: 00007f32c7a25fa0 R15: 00007ffe4acf6648 ---------------- Code disassembly (best guess), 3 bytes skipped: 0: 7f 39 jg 0x3b 2: cf iret 3: 7f 2a jg 0x2f 5: 81 ff ff 00 00 00 cmp $0xff,%edi b: 0f 93 c1 setae %cl e: 84 c0 test %al,%al 10: 0f 95 c0 setne %al 13: 08 c8 or %cl,%al 15: 74 58 je 0x6f 17: 65 8b 05 b4 83 dc 11 mov %gs:0x11dc83b4(%rip),%eax # 0x11dc83d2 1e: f7 df neg %edi 20: 65 01 3d ab 83 dc 11 add %edi,%gs:0x11dc83ab(%rip) # 0x11dc83d2 * 27: 5b pop %rbx <-- trapping instruction 28: 5d pop %rbp 29: e9 14 7b 49 0a jmp 0xa497b42 2e: cc int3 2f: 90 nop 30: e8 dd 5f 40 03 call 0x3406012 35: 85 c0 test %eax,%eax 37: 74 33 je 0x6c 39: 48 rex.W 3a: c7 .byte 0xc7 3b: c0 .byte 0xc0 3c: 84 .byte 0x84