================================ WARNING: inconsistent lock state syzkaller #0 Tainted: G L -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.6.937/10051 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff8880419be260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1715 [inline] ffff8880419be260 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 lock_sock_nested+0x41/0x100 net/core/sock.c:3879 lock_sock include/net/sock.h:1715 [inline] x25_release+0xa0/0x3d0 net/x25/af_x25.c:629 __sock_release+0xa0/0x1f0 net/socket.c:735 sock_close+0x1c/0x30 net/socket.c:1529 __fput+0x408/0xa40 fs/file_table.c:513 fput_close_sync+0x11f/0x240 fs/file_table.c:619 filp_close_sync+0x6e/0xa0 fs/open.c:1897 __range_close fs/file.c:919 [inline] __do_sys_close_range fs/file.c:1003 [inline] __se_sys_close_range+0xa77/0xef0 fs/file.c:954 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: 78818 hardirqs last enabled at (78818): [] __local_bh_enable_ip+0xd6/0x140 kernel/softirq.c:478 hardirqs last disabled at (78817): [] __local_bh_enable_ip+0x72/0x140 kernel/softirq.c:455 softirqs last enabled at (75894): [] __do_softirq kernel/softirq.c:679 [inline] softirqs last enabled at (75894): [] invoke_softirq kernel/softirq.c:519 [inline] softirqs last enabled at (75894): [] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758 softirqs last disabled at (78667): [] __do_softirq kernel/softirq.c:679 [inline] softirqs last disabled at (78667): [] invoke_softirq kernel/softirq.c:519 [inline] softirqs last disabled at (78667): [] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758 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.6.937/10051: 4, last CPU#0: #0: ffff888036e24460 (sb_writers#5){.+.+}-{0:0}, at: vfs_coredump+0xb41/0x10f0 fs/coredump.c:1306 #1: ffff88807c2e6408 (&sb->s_type->i_mutex_key#16){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #1: ffff88807c2e6408 (&sb->s_type->i_mutex_key#16){+.+.}-{4:4}, at: shmem_file_write_iter+0x7f/0x120 mm/shmem.c:3635 #2: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: __update_page_owner_handle+0x5a/0x580 mm/page_owner.c:273 #3: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #3: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6359 stack backtrace: CPU: 0 UID: 0 PID: 10051 Comm: syz.6.937 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:4086 valid_state+0xbe/0xf0 kernel/locking/lockdep.c:4100 mark_lock_irq+0x36/0x380 kernel/locking/lockdep.c:4311 mark_lock+0x117/0x190 kernel/locking/lockdep.c:4797 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0x71e/0x2de0 kernel/locking/lockdep.c:5242 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 lock_sock_nested+0x41/0x100 net/core/sock.c:3879 lock_sock include/net/sock.h:1715 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6335 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6360 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7868 napi_poll net/core/dev.c:7931 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8088 handle_softirqs+0x223/0x840 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:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 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:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947 Code: ff ff ff e8 80 48 4b 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e2 82 f3 12 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 3f 5c 4e 0a cc 48 8d 3d 37 70 d9 RSP: 0018:ffffc90008b560c0 EFLAGS: 00000296 RAX: 0b6a63c949226000 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 000000008955da8e RSI: ffffffff8e717a62 RDI: ffffffff8c6e2380 RBP: ffff8880287a3e80 R08: ffffffff8245b85a R09: 0000000000000000 R10: ffff8880287a47a0 R11: ffffffff81b336d0 R12: ffffffff8fd5a2a0 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:309 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] __update_page_owner_handle+0x77/0x580 mm/page_owner.c:273 __set_page_owner+0x10a/0x4c0 mm/page_owner.c:360 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1854 prep_new_page mm/page_alloc.c:1862 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3933 __alloc_frozen_pages_noprof+0x1fc/0x400 mm/page_alloc.c:5477 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2511 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2530 shmem_alloc_folio mm/shmem.c:2141 [inline] shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:2183 shmem_get_folio_gfp+0x594/0x1330 mm/shmem.c:2736 shmem_get_folio mm/shmem.c:2835 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3470 generic_perform_write+0x2d5/0x8e0 mm/filemap.c:4392 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3645 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_write_iter fs/coredump.c:1354 [inline] dump_emit_page fs/coredump.c:1527 [inline] dump_user_range+0x715/0xca0 fs/coredump.c:1595 elf_core_dump+0x346a/0x3a70 fs/binfmt_elf.c:2106 coredump_write fs/coredump.c:1146 [inline] do_coredump+0x5d99/0x6910 fs/coredump.c:1231 vfs_coredump+0xb41/0x10f0 fs/coredump.c:1306 get_signal+0x108f/0x12c0 kernel/signal.c:3097 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+0x2c0/0x920 kernel/entry/common.c:152 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fe61d99e1e1 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: 00007fe61dc26090 RCX: 00007fe61d99e1d9 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007fe61da35888 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fe61dc26128 R14: 00007fe61dc26090 R15: 00007fffd608dca8 BUG: sleeping function called from invalid context at net/core/sock.c:3881 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 10051, name: syz.6.937 preempt_count: 100, expected: 0 RCU nest depth: 2, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:486 [inline] [] handle_softirqs+0xab/0x840 kernel/softirq.c:621 CPU: 0 UID: 0 PID: 10051 Comm: syz.6.937 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:9200 lock_sock_nested+0x56/0x100 net/core/sock.c:3881 lock_sock include/net/sock.h:1715 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6335 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6360 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7868 napi_poll net/core/dev.c:7931 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8088 handle_softirqs+0x223/0x840 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:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 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:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947 Code: ff ff ff e8 80 48 4b 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e2 82 f3 12 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 3f 5c 4e 0a cc 48 8d 3d 37 70 d9 RSP: 0018:ffffc90008b560c0 EFLAGS: 00000296 RAX: 0b6a63c949226000 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 000000008955da8e RSI: ffffffff8e717a62 RDI: ffffffff8c6e2380 RBP: ffff8880287a3e80 R08: ffffffff8245b85a R09: 0000000000000000 R10: ffff8880287a47a0 R11: ffffffff81b336d0 R12: ffffffff8fd5a2a0 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:309 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] __update_page_owner_handle+0x77/0x580 mm/page_owner.c:273 __set_page_owner+0x10a/0x4c0 mm/page_owner.c:360 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1854 prep_new_page mm/page_alloc.c:1862 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3933 __alloc_frozen_pages_noprof+0x1fc/0x400 mm/page_alloc.c:5477 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2511 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2530 shmem_alloc_folio mm/shmem.c:2141 [inline] shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:2183 shmem_get_folio_gfp+0x594/0x1330 mm/shmem.c:2736 shmem_get_folio mm/shmem.c:2835 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3470 generic_perform_write+0x2d5/0x8e0 mm/filemap.c:4392 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3645 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_write_iter fs/coredump.c:1354 [inline] dump_emit_page fs/coredump.c:1527 [inline] dump_user_range+0x715/0xca0 fs/coredump.c:1595 elf_core_dump+0x346a/0x3a70 fs/binfmt_elf.c:2106 coredump_write fs/coredump.c:1146 [inline] do_coredump+0x5d99/0x6910 fs/coredump.c:1231 vfs_coredump+0xb41/0x10f0 fs/coredump.c:1306 get_signal+0x108f/0x12c0 kernel/signal.c:3097 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+0x2c0/0x920 kernel/entry/common.c:152 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fe61d99e1e1 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: 00007fe61dc26090 RCX: 00007fe61d99e1d9 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007fe61da35888 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fe61dc26128 R14: 00007fe61dc26090 R15: 00007fffd608dca8 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: ff ljmp (bad) 1: e8 80 48 4b 0a call 0xa4b4886 6: f7 44 24 10 00 02 00 testl $0x200,0x10(%rsp) d: 00 e: 0f 84 38 ff ff ff je 0xffffff4c 14: 65 48 8b 05 e2 82 f3 mov %gs:0x12f382e2(%rip),%rax # 0x12f382fe 1b: 12 1c: 48 3b 44 24 50 cmp 0x50(%rsp),%rax 21: 75 33 jne 0x56 23: fb sti 24: 48 83 c4 58 add $0x58,%rsp * 28: 5b pop %rbx <-- trapping instruction 29: 41 5c pop %r12 2b: 41 5d pop %r13 2d: 41 5e pop %r14 2f: 41 5f pop %r15 31: 5d pop %rbp 32: e9 3f 5c 4e 0a jmp 0xa4e5c76 37: cc int3 38: 48 rex.W 39: 8d .byte 0x8d 3a: 3d .byte 0x3d 3b: 37 (bad) 3c: 70 d9 jo 0x17