------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(1) WARNING: kernel/locking/lockdep.c:238 at hlock_class kernel/locking/lockdep.c:238 [inline], CPU#1: syz.2.1567/9978 WARNING: kernel/locking/lockdep.c:238 at check_wait_context kernel/locking/lockdep.c:4854 [inline], CPU#1: syz.2.1567/9978 WARNING: kernel/locking/lockdep.c:238 at __lock_acquire+0x382/0x2cf0 kernel/locking/lockdep.c:5187, CPU#1: syz.2.1567/9978 Modules linked in: CPU: 1 UID: 0 PID: 9978 Comm: syz.2.1567 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:hlock_class kernel/locking/lockdep.c:238 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline] RIP: 0010:__lock_acquire+0x389/0x2cf0 kernel/locking/lockdep.c:5187 Code: 83 3d da 46 d6 18 00 75 27 90 e8 62 fd 2d 03 85 c0 74 1c 83 3d 8b fd b4 0e 00 75 13 48 8d 3d 0e 5a b8 0e 48 c7 c6 83 5c 35 8e <67> 48 0f b9 3a 90 31 c0 0f b6 98 c4 00 00 00 41 8b 45 20 25 ff 1f RSP: 0018:ffffc90000a089b8 EFLAGS: 00010046 RAX: 0000000000000001 RBX: 0000000000042000 RCX: ffff88807e9cddc0 RDX: 0000000000000100 RSI: ffffffff8e355c83 RDI: ffffffff905b18d0 RBP: 0000000000000001 R08: ffffffff9057bc43 R09: 1ffffffff20af788 R10: dffffc0000000000 R11: fffffbfff20af789 R12: 0000000000000a9b R13: ffff88807e9ce9e0 R14: ffff88807e9cddc0 R15: ffff88807e9ce968 FS: 00007f8eaf4696c0(0000) GS:ffff888125045000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f481b627dac CR3: 0000000053d5b000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158 spin_lock include/linux/spinlock.h:342 [inline] tcp_tsq_handler+0x29/0x200 net/ipv4/tcp_output.c:1291 tcp_tsq_workfn+0x384/0x410 net/ipv4/tcp_output.c:1325 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 bh_worker+0x44e/0x840 kernel/workqueue.c:3708 tasklet_action+0xc/0x70 kernel/softirq.c:965 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:rcu_read_lock include/linux/rcupdate.h:841 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1183 [inline] RIP: 0010:unwind_next_frame+0xc0/0x2550 arch/x86/kernel/unwind_orc.c:495 Code: 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 55 e8 c4 34 2b 00 48 83 c4 08 e8 4b b8 5b 0a 85 c0 74 3a e8 02 5f 34 00 84 c0 <75> 31 e8 39 b8 5b 0a 85 c0 74 28 80 3d a5 61 c9 0e 00 75 1f c6 05 RSP: 0018:ffffc9001cc36a00 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff823478ec RCX: 0000000080000001 RDX: 000000005a44979c RSI: ffffffff8c4bd660 RDI: ffffffff8c4bd620 RBP: 1ffff92003986d5c R08: ffffffff8177827f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59d60 R12: dffffc0000000000 R13: ffffffff8177827f R14: ffffc9001cc36aa8 R15: 1ffff92003986d55 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x1c5/0x640 mm/slub.c:6692 skb_kfree_head net/core/skbuff.c:1083 [inline] skb_free_head net/core/skbuff.c:1095 [inline] skb_release_data+0x85e/0xab0 net/core/skbuff.c:1122 skb_release_all net/core/skbuff.c:1197 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1211 kfree_skb_reason include/linux/skbuff.h:1323 [inline] kfree_skb include/linux/skbuff.h:1332 [inline] __rtnl_unlock+0x95/0xf0 net/core/rtnetlink.c:148 netdev_run_todo+0x2e8/0x10d0 net/core/dev.c:11718 rtnl_unlock net/core/rtnetlink.c:157 [inline] rtnl_nets_unlock net/core/rtnetlink.c:354 [inline] rtnl_newlink+0x16e0/0x1bd0 net/core/rtnetlink.c:4160 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] ____sys_sendmsg+0x54e/0x850 net/socket.c:2709 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2763 __sys_sendmsg net/socket.c:2795 [inline] __do_sys_sendmsg net/socket.c:2800 [inline] __se_sys_sendmsg net/socket.c:2798 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2798 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8eae59e0d9 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:00007f8eaf469028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8eae826090 RCX: 00007f8eae59e0d9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000006 RBP: 00007f8eae635024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8eae826128 R14: 00007f8eae826090 R15: 00007ffd7b049288 ---------------- Code disassembly (best guess): 0: 83 3d da 46 d6 18 00 cmpl $0x0,0x18d646da(%rip) # 0x18d646e1 7: 75 27 jne 0x30 9: 90 nop a: e8 62 fd 2d 03 call 0x32dfd71 f: 85 c0 test %eax,%eax 11: 74 1c je 0x2f 13: 83 3d 8b fd b4 0e 00 cmpl $0x0,0xeb4fd8b(%rip) # 0xeb4fda5 1a: 75 13 jne 0x2f 1c: 48 8d 3d 0e 5a b8 0e lea 0xeb85a0e(%rip),%rdi # 0xeb85a31 23: 48 c7 c6 83 5c 35 8e mov $0xffffffff8e355c83,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 90 nop 30: 31 c0 xor %eax,%eax 32: 0f b6 98 c4 00 00 00 movzbl 0xc4(%rax),%ebx 39: 41 8b 45 20 mov 0x20(%r13),%eax 3d: 25 .byte 0x25 3e: ff 1f lcall *(%rdi)