Oops: general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:snd_usbmidi_do_output+0x199/0x560 sound/usb/midi.c:310 Code: 5c 24 48 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 48 7c ec f8 48 8b 1b 4c 8d ab 88 00 00 00 4d 89 ef 49 c1 ef 03 <43> 0f b6 04 37 84 c0 0f 85 44 02 00 00 41 c7 45 00 00 00 00 00 48 RSP: 0018:ffffc90000007ab8 EFLAGS: 00010006 RAX: 1ffff11008d08901 RBX: 0000000000000000 RCX: ffffffff8de95100 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000f34 R12: 0000000000000001 R13: 0000000000000088 R14: dffffc0000000000 R15: 0000000000000011 FS: 0000000000000000(0000) GS:ffff888125c12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f80abb56a40 CR3: 00000000792c8000 CR4: 00000000003526f0 Call Trace: snd_usbmidi_error_timer+0x316/0x660 sound/usb/midi.c:362 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 53 e8 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 b9 0d 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c2 RAX: 7e7f791984d21400 RBX: ffffffff81968488 RCX: 7e7f791984d21400 RDX: 0000000000000001 RSI: ffffffff8d9ba571 RDI: ffffffff8be33f80 RBP: ffffffff8de07eb8 R08: ffff8880b8632f9b R09: 1ffff110170c65f3 R10: dffffc0000000000 R11: ffffed10170c65f4 R12: ffffffff8fa3a730 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a20 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:744 start_kernel+0x3a9/0x410 init/main.c:1097 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:snd_usbmidi_do_output+0x199/0x560 sound/usb/midi.c:310 Code: 5c 24 48 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 48 7c ec f8 48 8b 1b 4c 8d ab 88 00 00 00 4d 89 ef 49 c1 ef 03 <43> 0f b6 04 37 84 c0 0f 85 44 02 00 00 41 c7 45 00 00 00 00 00 48 RSP: 0018:ffffc90000007ab8 EFLAGS: 00010006 RAX: 1ffff11008d08901 RBX: 0000000000000000 RCX: ffffffff8de95100 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000f34 R12: 0000000000000001 R13: 0000000000000088 R14: dffffc0000000000 R15: 0000000000000011 FS: 0000000000000000(0000) GS:ffff888125c12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f80abb56a40 CR3: 00000000792c8000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 5c pop %rsp 1: 24 48 and $0x48,%al 3: 48 89 d8 mov %rbx,%rax 6: 48 c1 e8 03 shr $0x3,%rax a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) f: 74 08 je 0x19 11: 48 89 df mov %rbx,%rdi 14: e8 48 7c ec f8 call 0xf8ec7c61 19: 48 8b 1b mov (%rbx),%rbx 1c: 4c 8d ab 88 00 00 00 lea 0x88(%rbx),%r13 23: 4d 89 ef mov %r13,%r15 26: 49 c1 ef 03 shr $0x3,%r15 * 2a: 43 0f b6 04 37 movzbl (%r15,%r14,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 44 02 00 00 jne 0x27b 37: 41 c7 45 00 00 00 00 movl $0x0,0x0(%r13) 3e: 00 3f: 48 rex.W