Oops: general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f] CPU: 1 UID: 0 PID: 55 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: usb_hub_wq hub_event 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 18 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:ffffc90000a08ab8 EFLAGS: 00010006 RAX: 1ffff1100be82601 RBX: 0000000000000000 RCX: ffff88801a5b0000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000141134 R12: 0000000000000001 R13: 0000000000000088 R14: dffffc0000000000 R15: 0000000000000011 FS: 0000000000000000(0000) GS:ffff888125d12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000212000 CR3: 0000000023df6000 CR4: 00000000003526f0 DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081 DR3: ffffffffefffff14 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: snd_usbmidi_error_timer+0x316/0x660 sound/usb/midi.c:362 call_timer_fn+0x17e/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+0x286/0x870 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:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg+0xc3/0x230 arch/x86/kernel/unwind_orc.c:403 Code: 85 3c 01 00 00 41 83 3f 00 0f 95 c0 4c 39 c3 0f 96 c1 20 c1 4d 39 c6 0f 97 c0 20 c8 3c 01 75 18 49 8d 40 08 48 39 d8 0f 97 c1 <4c> 39 f0 0f 96 c0 84 c1 0f 85 c3 00 00 00 49 8d 7f 28 48 89 f8 48 RSP: 0018:ffffc90000bf64c0 EFLAGS: 00000206 RAX: ffffc90000bf6cb8 RBX: ffffc90000bf0000 RCX: 0000000000000001 RDX: ffffc90000bf6628 RSI: dffffc0000000000 RDI: ffffc90000bf65e8 RBP: 1ffff9200017ecbd R08: ffffc90000bf6cb0 R09: 0000000000000000 R10: ffffc90000bf6638 R11: fffff5200017ecc9 R12: 1ffff9200017ecbe R13: 1ffff9200017ecbf R14: ffffc90000bf8000 R15: ffffc90000bf65e8 unwind_next_frame+0x17c4/0x2390 arch/x86/kernel/unwind_orc.c:-1 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kfree+0x18e/0x440 mm/slub.c:4894 free_urb_and_buffer sound/usb/midi.c:1309 [inline] snd_usbmidi_out_endpoint_clear+0x5f1/0x820 sound/usb/midi.c:1402 snd_usbmidi_out_endpoint_delete sound/usb/midi.c:1410 [inline] snd_usbmidi_free sound/usb/midi.c:1528 [inline] snd_usbmidi_rawmidi_free+0x6d/0x160 sound/usb/midi.c:1591 snd_rawmidi_free+0x3bf/0x410 sound/core/rawmidi.c:1934 snd_rawmidi_dev_free+0x38/0x50 sound/core/rawmidi.c:1945 __snd_device_free+0x1d5/0x2e0 sound/core/device.c:76 snd_device_free_all+0xcf/0x180 sound/core/device.c:233 snd_card_do_free sound/core/init.c:587 [inline] release_card_device+0x75/0x1b0 sound/core/init.c:153 device_release+0x99/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 snd_card_free_when_closed sound/core/init.c:618 [inline] snd_card_free+0x110/0x190 sound/core/init.c:650 usb_audio_probe+0x193f/0x1e10 sound/usb/card.c:1034 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2694 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 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 18 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:ffffc90000a08ab8 EFLAGS: 00010006 RAX: 1ffff1100be82601 RBX: 0000000000000000 RCX: ffff88801a5b0000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000141134 R12: 0000000000000001 R13: 0000000000000088 R14: dffffc0000000000 R15: 0000000000000011 FS: 0000000000000000(0000) GS:ffff888125d12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000212000 CR3: 0000000023df6000 CR4: 00000000003526f0 DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081 DR3: ffffffffefffff14 DR6: 00000000ffff0ff0 DR7: 0000000000000400 ---------------- 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 18 7c ec f8 call 0xf8ec7c31 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