Hello,

syzbot found the following crash on:

HEAD commit: 9a33b369 usb-fuzzer: main usb gadget fuzzer driver git tree: https://github.com/google/kasan/tree/usb-fuzzer console output: https://syzkaller.appspot.com/x/log.txt?x=14edefa7200000 kernel config: https://syzkaller.appspot.com/x/.config?x=23e37f59d94ddd15 dashboard link: https://syzkaller.appspot.com/bug?extid=90cf07b4a2473213d16b compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15aba2b7200000

IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+90cf07b4a2473213d16b@syzkaller.appspotmail.com

snd_usb_toneport: probe of 6-1:0.0 failed with error -71 snd_usb_toneport 2-1:0.0: Line 6 POD Studio UX2 now disconnected usb 5-1: USB disconnect, device number 5 list_del corruption. prev->next should be ffff8880a725e9a8, but was ffff8880a725e228 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:51! invalid opcode: 0000 [#1] SMP KASAN PTI usb 6-1: USB disconnect, device number 5 CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.1.0-rc4-319354-g9a33b36 #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:__list_del_entry_valid.cold+0xf/0x55 lib/list_debug.c:51 Code: e8 69 e7 e9 fd 0f 0b 48 89 f1 48 c7 c7 00 94 b3 8e 4c 89 e6 e8 55 e7 e9 fd 0f 0b 48 89 ee 48 c7 c7 a0 95 b3 8e e8 44 e7 e9 fd <0f> 0b 4c 89 ea 48 89 ee 48 c7 c7 e0 94 b3 8e e8 30 e7 e9 fd 0f 0b RSP: 0018:ffff8880a84b7118 EFLAGS: 00010282 RAX: 0000000000000054 RBX: ffff8880a725e8b0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815b1e42 RDI: ffffed1015096e15 RBP: ffff8880a725e9a8 R08: 0000000000000054 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809cb90868 R13: ffff8880a7068e98 R14: ffff8880a725e8b0 R15: ffff8880a725e998 FS: 0000000000000000(0000) GS:ffff8880ad000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff9de9dfc8 CR3: 00000000963ea000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] snd_info_free_entry+0x137/0x340 sound/core/info.c:795 snd_info_card_free+0x43/0x90 sound/core/info.c:606 snd_card_do_free sound/core/init.c:469 [inline] release_card_device+0x8b/0x100 sound/core/init.c:156 device_release+0x7d/0x210 drivers/base/core.c:1064 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:67 [inline] kobject_put+0x1df/0x4f0 lib/kobject.c:708 put_device+0x21/0x30 drivers/base/core.c:2205 snd_card_free_when_closed+0x3a/0x50 sound/core/init.c:493 line6_disconnect.cold+0xa3/0xbc sound/usb/line6/driver.c:833 line6_probe+0xb23/0x1150 sound/usb/line6/driver.c:799 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266 really_probe+0x2da/0xb10 drivers/base/dd.c:509 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778 usb 1-1: new high-speed USB device number 6 using dummy_hcd bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454 __device_attach+0x223/0x3a0 drivers/base/dd.c:844 usb 6-1: new high-speed USB device number 6 using dummy_hcd usb 5-1: new high-speed USB device number 6 using dummy_hcd bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514 device_add+0xad2/0x16e0 drivers/base/core.c:2106 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534 hub_port_connect drivers/usb/core/hub.c:5089 [inline] hub_port_connect_change drivers/usb/core/hub.c:5204 [inline] port_event drivers/usb/core/hub.c:5350 [inline] hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269 process_scheduled_works kernel/workqueue.c:2331 [inline] worker_thread+0x7b0/0xe20 kernel/workqueue.c:2417 kthread+0x313/0x420 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Modules linked in: ---[ end trace 8111524f564d7b8a ]--- RIP: 0010:__list_del_entry_valid.cold+0xf/0x55 lib/list_debug.c:51 Code: e8 69 e7 e9 fd 0f 0b 48 89 f1 48 c7 c7 00 94 b3 8e 4c 89 e6 e8 55 e7 e9 fd 0f 0b 48 89 ee 48 c7 c7 a0 95 b3 8e e8 44 e7 e9 fd <0f> 0b 4c 89 ea 48 89 ee 48 c7 c7 e0 94 b3 8e e8 30 e7 e9 fd 0f 0b RSP: 0018:ffff8880a84b7118 EFLAGS: 00010282 RAX: 0000000000000054 RBX: ffff8880a725e8b0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815b1e42 RDI: ffffed1015096e15 RBP: ffff8880a725e9a8 R08: 0000000000000054 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809cb90868 R13: ffff8880a7068e98 R14: ffff8880a725e8b0 R15: ffff8880a725e998 FS: 0000000000000000(0000) GS:ffff8880ad000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff9de9dfc8 CR3: 00000000963ea000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

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