================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.0.254/5216 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88807566a130 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline] ffff88807566a130 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 lock_sock_nested+0x44/0x100 net/core/sock.c:3505 lock_sock include/net/sock.h:1805 [inline] x25_bind+0x1aa/0x3e0 net/x25/af_x25.c:698 __sys_bind+0x2e9/0x3e0 net/socket.c:1811 __do_sys_bind net/socket.c:1822 [inline] __se_sys_bind net/socket.c:1820 [inline] __x64_sys_bind+0x76/0x80 net/socket.c:1820 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 irq event stamp: 8890 hardirqs last enabled at (8890): [] __local_bh_enable_ip+0x136/0x1c0 kernel/softirq.c:426 hardirqs last disabled at (8889): [] __local_bh_enable_ip+0xd7/0x1c0 kernel/softirq.c:403 softirqs last enabled at (6028): [] __do_softirq kernel/softirq.c:630 [inline] softirqs last enabled at (6028): [] invoke_softirq kernel/softirq.c:470 [inline] softirqs last enabled at (6028): [] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 softirqs last disabled at (8817): [] __do_softirq kernel/softirq.c:630 [inline] softirqs last disabled at (8817): [] invoke_softirq kernel/softirq.c:470 [inline] softirqs last disabled at (8817): [] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** 4 locks held by syz.0.254/5216: #0: ffff88801746a6d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] #0: ffff88801746a6d8 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x17f/0x380 mm/gup.c:1700 #1: ffff88807e30c318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #1: ffff88807e30c318 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: finish_fault+0x484/0x8c0 mm/memory.c:4492 #2: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #2: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #2: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: folio_memcg_lock+0x7d/0x320 mm/memcontrol.c:2101 #3: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #3: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: netif_receive_skb_core+0x30/0x230 net/core/dev.c:5643 stack backtrace: CPU: 1 PID: 5216 Comm: syz.0.254 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:3974 mark_lock_irq+0xa9/0x900 kernel/locking/lockdep.c:4177 mark_lock+0x208/0x320 kernel/locking/lockdep.c:4633 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0xce0/0x7c40 kernel/locking/lockdep.c:5017 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 lock_sock_nested+0x44/0x100 net/core/sock.c:3505 lock_sock include/net/sock.h:1805 [inline] x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 x25_lapb_receive_frame+0x1a3/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5619 [inline] netif_receive_skb_core+0x166/0x230 net/core/dev.c:5644 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x460 net/core/dev.c:6628 napi_poll net/core/dev.c:6695 [inline] net_rx_action+0x622/0xbc0 net/core/dev.c:6809 handle_softirqs+0x291/0x910 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:instrument_atomic_read include/linux/instrumented.h:72 [inline] RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] RIP: 0010:folio_memcg_lock+0x1c4/0x320 mm/memcontrol.c:2116 Code: 00 9c 8f 44 24 60 f7 44 24 60 00 02 00 00 c6 44 03 08 f8 0f 85 8d 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 4d 8d a7 40 09 00 00 <4c> 89 e7 be 04 00 00 00 e8 3f 6e f9 ff 4c 89 e0 48 c1 e8 03 48 b9 RSP: 0018:ffffc9001ba577e0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200374af00 RCX: 22c53b4499c11a00 RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0 RBP: ffffc9001ba578b0 R08: ffffffff90b10247 R09: 1ffffffff2162048 R10: dffffc0000000000 R11: fffffbfff2162049 R12: ffff88802e87c940 R13: 0000000000000286 R14: 1ffff9200374af00 R15: ffff88802e87c000 page_add_file_rmap+0xea/0x1550 mm/rmap.c:1293 do_set_pte+0x2f4/0x460 mm/memory.c:4422 finish_fault+0x7ba/0x8c0 mm/memory.c:4497 do_read_fault mm/memory.c:4633 [inline] do_fault mm/memory.c:4758 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x2636/0x3d40 mm/memory.c:5292 faultin_page mm/gup.c:1026 [inline] __get_user_pages+0x40d/0xec0 mm/gup.c:1250 populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607 __mm_populate+0x25c/0x380 mm/gup.c:1721 mm_populate include/linux/mm.h:2891 [inline] vm_mmap_pgoff+0x212/0x2d0 mm/util.c:525 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f200ab9e0d9 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:00007f200bb49028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f200ae25fa0 RCX: 00007f200ab9e0d9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f200ac35024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f200ae26038 R14: 00007f200ae25fa0 R15: 00007fff8b79f638 BUG: sleeping function called from invalid context at net/core/sock.c:3507 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5216, name: syz.0.254 preempt_count: 101, expected: 0 RCU nest depth: 2, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<0000000000000000>] 0x0 CPU: 1 PID: 5216 Comm: syz.0.254 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 __might_resched+0x489/0x5f0 kernel/sched/core.c:9970 lock_sock_nested+0x59/0x100 net/core/sock.c:3507 lock_sock include/net/sock.h:1805 [inline] x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 x25_lapb_receive_frame+0x1a3/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5619 [inline] netif_receive_skb_core+0x166/0x230 net/core/dev.c:5644 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x460 net/core/dev.c:6628 napi_poll net/core/dev.c:6695 [inline] net_rx_action+0x622/0xbc0 net/core/dev.c:6809 handle_softirqs+0x291/0x910 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:instrument_atomic_read include/linux/instrumented.h:72 [inline] RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] RIP: 0010:folio_memcg_lock+0x1c4/0x320 mm/memcontrol.c:2116 Code: 00 9c 8f 44 24 60 f7 44 24 60 00 02 00 00 c6 44 03 08 f8 0f 85 8d 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 4d 8d a7 40 09 00 00 <4c> 89 e7 be 04 00 00 00 e8 3f 6e f9 ff 4c 89 e0 48 c1 e8 03 48 b9 RSP: 0018:ffffc9001ba577e0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200374af00 RCX: 22c53b4499c11a00 RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0 RBP: ffffc9001ba578b0 R08: ffffffff90b10247 R09: 1ffffffff2162048 R10: dffffc0000000000 R11: fffffbfff2162049 R12: ffff88802e87c940 R13: 0000000000000286 R14: 1ffff9200374af00 R15: ffff88802e87c000 page_add_file_rmap+0xea/0x1550 mm/rmap.c:1293 do_set_pte+0x2f4/0x460 mm/memory.c:4422 finish_fault+0x7ba/0x8c0 mm/memory.c:4497 do_read_fault mm/memory.c:4633 [inline] do_fault mm/memory.c:4758 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x2636/0x3d40 mm/memory.c:5292 faultin_page mm/gup.c:1026 [inline] __get_user_pages+0x40d/0xec0 mm/gup.c:1250 populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607 __mm_populate+0x25c/0x380 mm/gup.c:1721 mm_populate include/linux/mm.h:2891 [inline] vm_mmap_pgoff+0x212/0x2d0 mm/util.c:525 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f200ab9e0d9 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:00007f200bb49028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f200ae25fa0 RCX: 00007f200ab9e0d9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f200ac35024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f200ae26038 R14: 00007f200ae25fa0 R15: 00007fff8b79f638 ---------------- Code disassembly (best guess): 0: 00 9c 8f 44 24 60 f7 add %bl,-0x89fdbbc(%rdi,%rcx,4) 7: 44 24 60 rex.R and $0x60,%al a: 00 02 add %al,(%rdx) c: 00 00 add %al,(%rax) e: c6 44 03 08 f8 movb $0xf8,0x8(%rbx,%rax,1) 13: 0f 85 8d 00 00 00 jne 0xa6 19: 41 f7 c5 00 02 00 00 test $0x200,%r13d 20: 74 01 je 0x23 22: fb sti 23: 4d 8d a7 40 09 00 00 lea 0x940(%r15),%r12 * 2a: 4c 89 e7 mov %r12,%rdi <-- trapping instruction 2d: be 04 00 00 00 mov $0x4,%esi 32: e8 3f 6e f9 ff call 0xfff96e76 37: 4c 89 e0 mov %r12,%rax 3a: 48 c1 e8 03 shr $0x3,%rax 3e: 48 rex.W 3f: b9 .byte 0xb9