================================ WARNING: inconsistent lock state syzkaller #0 Tainted: G L -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.8.2379/18770 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88807a0dc260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] ffff88807a0dc260 (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: 111442 hardirqs last enabled at (111442): [] __local_bh_enable_ip+0xd6/0x140 kernel/softirq.c:478 hardirqs last disabled at (111441): [] __local_bh_enable_ip+0x72/0x140 kernel/softirq.c:455 softirqs last enabled at (107858): [] __do_softirq kernel/softirq.c:679 [inline] softirqs last enabled at (107858): [] invoke_softirq kernel/softirq.c:519 [inline] softirqs last enabled at (107858): [] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767 softirqs last disabled at (111399): [] __do_softirq kernel/softirq.c:679 [inline] softirqs last disabled at (111399): [] invoke_softirq kernel/softirq.c:519 [inline] softirqs last disabled at (111399): [] __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 syz.8.2379/18770: 3, last CPU#1: #0: ffff888028b76460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1126 [inline] #0: ffff888028b76460 (sb_writers#5){.+.+}-{0:0}, at: vfs_coredump+0x3766/0x4530 fs/coredump.c:1195 #1: ffff888036370e98 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline] #1: ffff888036370e98 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: shmem_file_write_iter+0x7f/0x120 mm/shmem.c:3429 #2: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8eb5c8a0 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6269 stack backtrace: CPU: 1 UID: 0 PID: 18770 Comm: syz.8.2379 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline] RIP: 0010:__pvclock_clocksource_read arch/x86/kernel/pvclock.c:77 [inline] RIP: 0010:pvclock_clocksource_read_nowd+0x40/0xf0 arch/x86/kernel/pvclock.c:120 Code: 73 53 89 d9 48 d3 e0 83 e5 fe 4c 89 34 24 48 f7 24 24 48 0f ac d0 20 48 8b 4f 10 0f b6 57 1d 8b 37 39 f5 89 f5 74 74 0f 01 f9 <66> 90 48 89 c1 48 89 d0 48 c1 e0 20 48 09 c8 48 2b 47 08 44 8b 77 RSP: 0000:ffffc9000474e2c8 EFLAGS: 00000283 RAX: 00000000db2229aa RBX: 0000000000140cca RCX: 0000000000000001 RDX: 0000000000000167 RSI: 0000000000000000 RDI: ffffffff93759040 RBP: 0000000000000008 R08: ffffffff9059037f R09: 0000000000000000 R10: ffffed100a3b8200 R11: fffffbfff20b2070 R12: ffff888051dc1000 R13: dffffc0000000000 R14: ffffea0001477040 R15: 0000000000000001 kvm_sched_clock_read+0x11/0x20 arch/x86/kernel/kvmclock.c:113 local_clock_noinstr+0xc/0xe0 kernel/sched/clock.c:307 local_clock+0x11/0x30 kernel/sched/clock.c:321 __set_page_owner+0x7f/0x4c0 mm/page_owner.c:356 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1932 [inline] shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:1974 shmem_get_folio_gfp+0x5da/0x16d0 mm/shmem.c:2527 shmem_get_folio mm/shmem.c:2633 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3264 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4374 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3439 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_emit_page fs/coredump.c:1293 [inline] dump_user_range+0xc19/0x12c0 fs/coredump.c:1367 elf_core_dump+0x3485/0x3a90 fs/binfmt_elf.c:2106 coredump_write+0x1290/0x1960 fs/coredump.c:1047 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3766/0x4530 fs/coredump.c:1195 get_signal+0x1094/0x12c0 kernel/signal.c:3024 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop kernel/entry/common.c:101 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline] irqentry_exit+0x2ba/0x910 kernel/entry/common.c:165 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fcdbbb9e0e1 Code: 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007fcdbbe26090 RCX: 00007fcdbbb9e0d9 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007fcdbbc35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fcdbbe26128 R14: 00007fcdbbe26090 R15: 00007ffe22061168 BUG: sleeping function called from invalid context at net/core/sock.c:3829 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 18770, name: syz.8.2379 preempt_count: 101, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] rmqueue_pcplist mm/page_alloc.c:3380 [inline] [] rmqueue mm/page_alloc.c:3421 [inline] [] get_page_from_freelist+0x645/0x2280 mm/page_alloc.c:3940 CPU: 1 UID: 0 PID: 18770 Comm: syz.8.2379 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline] RIP: 0010:__pvclock_clocksource_read arch/x86/kernel/pvclock.c:77 [inline] RIP: 0010:pvclock_clocksource_read_nowd+0x40/0xf0 arch/x86/kernel/pvclock.c:120 Code: 73 53 89 d9 48 d3 e0 83 e5 fe 4c 89 34 24 48 f7 24 24 48 0f ac d0 20 48 8b 4f 10 0f b6 57 1d 8b 37 39 f5 89 f5 74 74 0f 01 f9 <66> 90 48 89 c1 48 89 d0 48 c1 e0 20 48 09 c8 48 2b 47 08 44 8b 77 RSP: 0000:ffffc9000474e2c8 EFLAGS: 00000283 RAX: 00000000db2229aa RBX: 0000000000140cca RCX: 0000000000000001 RDX: 0000000000000167 RSI: 0000000000000000 RDI: ffffffff93759040 RBP: 0000000000000008 R08: ffffffff9059037f R09: 0000000000000000 R10: ffffed100a3b8200 R11: fffffbfff20b2070 R12: ffff888051dc1000 R13: dffffc0000000000 R14: ffffea0001477040 R15: 0000000000000001 kvm_sched_clock_read+0x11/0x20 arch/x86/kernel/kvmclock.c:113 local_clock_noinstr+0xc/0xe0 kernel/sched/clock.c:307 local_clock+0x11/0x30 kernel/sched/clock.c:321 __set_page_owner+0x7f/0x4c0 mm/page_owner.c:356 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1932 [inline] shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:1974 shmem_get_folio_gfp+0x5da/0x16d0 mm/shmem.c:2527 shmem_get_folio mm/shmem.c:2633 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3264 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4374 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3439 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_emit_page fs/coredump.c:1293 [inline] dump_user_range+0xc19/0x12c0 fs/coredump.c:1367 elf_core_dump+0x3485/0x3a90 fs/binfmt_elf.c:2106 coredump_write+0x1290/0x1960 fs/coredump.c:1047 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3766/0x4530 fs/coredump.c:1195 get_signal+0x1094/0x12c0 kernel/signal.c:3024 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop kernel/entry/common.c:101 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline] irqentry_exit+0x2ba/0x910 kernel/entry/common.c:165 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fcdbbb9e0e1 Code: 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007fcdbbe26090 RCX: 00007fcdbbb9e0d9 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007fcdbbc35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fcdbbe26128 R14: 00007fcdbbe26090 R15: 00007ffe22061168 ---------------- Code disassembly (best guess): 0: 73 53 jae 0x55 2: 89 d9 mov %ebx,%ecx 4: 48 d3 e0 shl %cl,%rax 7: 83 e5 fe and $0xfffffffe,%ebp a: 4c 89 34 24 mov %r14,(%rsp) e: 48 f7 24 24 mulq (%rsp) 12: 48 0f ac d0 20 shrd $0x20,%rdx,%rax 17: 48 8b 4f 10 mov 0x10(%rdi),%rcx 1b: 0f b6 57 1d movzbl 0x1d(%rdi),%edx 1f: 8b 37 mov (%rdi),%esi 21: 39 f5 cmp %esi,%ebp 23: 89 f5 mov %esi,%ebp 25: 74 74 je 0x9b 27: 0f 01 f9 rdtscp * 2a: 66 90 xchg %ax,%ax <-- trapping instruction 2c: 48 89 c1 mov %rax,%rcx 2f: 48 89 d0 mov %rdx,%rax 32: 48 c1 e0 20 shl $0x20,%rax 36: 48 09 c8 or %rcx,%rax 39: 48 2b 47 08 sub 0x8(%rdi),%rax 3d: 44 rex.R 3e: 8b .byte 0x8b 3f: 77 .byte 0x77