Oops: general protection fault, probably for non-canonical address 0xdffffc0000000060: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000300-0x0000000000000307] CPU: 0 UID: 0 PID: 2840 Comm: syslogd Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:strcmp+0x5b/0xb0 lib/string.c:284 Code: fa 48 c1 e8 03 83 e2 07 42 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b ff 4c 8d 66 01 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 2c 41 3a 6c 24 ff 74 ae 19 c0 RSP: 0018:ffffc900000079b8 EFLAGS: 00010046 RAX: 0000000000000060 RBX: ffffffff878a8081 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000300 RDI: ffffffff878a8080 RBP: 0000000000000026 R08: 0000000000000001 R09: 0000000000000001 R10: ffff88811260800b R11: 0000000000000001 R12: 0000000000000301 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8eadbd88 FS: 00007f6d08bb2c80(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f63dafc2a60 CR3: 00000001179f8000 CR4: 00000000003506f0 Call Trace: count_matching_names kernel/locking/lockdep.c:878 [inline] register_lock_class+0x267/0x4b0 kernel/locking/lockdep.c:1344 __lock_acquire+0xa4/0x2890 kernel/locking/lockdep.c:5112 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 complete_with_flags kernel/sched/completion.c:25 [inline] complete+0x1d/0x200 kernel/sched/completion.c:52 transfer drivers/usb/gadget/udc/dummy_hcd.c:1523 [inline] dummy_timer+0x1c3e/0x3ad0 drivers/usb/gadget/udc/dummy_hcd.c:1979 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x208/0x940 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:kfree_skbmem+0x1a5/0x1f0 net/core/skbuff.c:1152 Code: c7 c0 10 6e 01 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 44 48 8b 3d 84 bc ce 02 48 89 ee e8 ec 05 a7 fb 5b <5d> 41 5c e9 d3 3d 4d fb e8 ce 3d 4d fb eb 89 e8 97 0e af fb e9 79 RSP: 0018:ffffc9000468fa10 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888135e67780 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffffffff88d04073 RDI: ffffffff878a7380 RBP: ffff888135e67780 R08: 0000000000000001 R09: 0000000000000001 R10: ffffc9000468fa08 R11: ffff888117a50aa8 R12: ffff888135e6785c R13: 00000000ffffffff R14: 0000000000000000 R15: ffff888135e67780 __kfree_skb net/core/skbuff.c:1197 [inline] consume_skb net/core/skbuff.c:1428 [inline] consume_skb+0xcc/0x100 net/core/skbuff.c:1422 __unix_dgram_recvmsg+0x779/0xc30 net/unix/af_unix.c:2658 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2675 sock_recvmsg_nosec net/socket.c:1078 [inline] sock_recvmsg+0x1f9/0x250 net/socket.c:1100 sock_read_iter+0x2b9/0x3b0 net/socket.c:1170 new_sync_read fs/read_write.c:491 [inline] vfs_read+0xa98/0xcf0 fs/read_write.c:572 ksys_read+0x1f8/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6d08d02407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffed45261c0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6d08bb2c80 RCX: 00007f6d08d02407 RDX: 00000000000000ff RSI: 000056100bb43300 RDI: 0000000000000000 RBP: 000056100bb432c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000056100bb43349 R13: 0000000000000000 R14: 000056100bb43300 R15: 0000560fe8721d98 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:strcmp+0x5b/0xb0 lib/string.c:284 Code: fa 48 c1 e8 03 83 e2 07 42 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b ff 4c 8d 66 01 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 2c 41 3a 6c 24 ff 74 ae 19 c0 RSP: 0018:ffffc900000079b8 EFLAGS: 00010046 RAX: 0000000000000060 RBX: ffffffff878a8081 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000300 RDI: ffffffff878a8080 RBP: 0000000000000026 R08: 0000000000000001 R09: 0000000000000001 R10: ffff88811260800b R11: 0000000000000001 R12: 0000000000000301 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8eadbd88 FS: 00007f6d08bb2c80(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f63dafc2a60 CR3: 00000001179f8000 CR4: 00000000003506f0 ---------------- Code disassembly (best guess): 0: fa cli 1: 48 c1 e8 03 shr $0x3,%rax 5: 83 e2 07 and $0x7,%edx 8: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax d: 38 d0 cmp %dl,%al f: 7f 04 jg 0x15 11: 84 c0 test %al,%al 13: 75 58 jne 0x6d 15: 48 89 f0 mov %rsi,%rax 18: 48 89 f2 mov %rsi,%rdx 1b: 0f b6 6b ff movzbl -0x1(%rbx),%ebp 1f: 4c 8d 66 01 lea 0x1(%rsi),%r12 23: 48 c1 e8 03 shr $0x3,%rax 27: 83 e2 07 and $0x7,%edx * 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction 2f: 38 d0 cmp %dl,%al 31: 7f 04 jg 0x37 33: 84 c0 test %al,%al 35: 75 2c jne 0x63 37: 41 3a 6c 24 ff cmp -0x1(%r12),%bpl 3c: 74 ae je 0xffffffec 3e: 19 c0 sbb %eax,%eax