Re: WARNING in rollback_registered_many (2)

On Wed, Aug 7, 2019 at 4:03 PM Andrey Konovalov [off-list ref] wrote:

On Fri, Apr 12, 2019 at 1:32 PM Andrey Konovalov [off-list ref] wrote:

quoted

On Fri, Apr 12, 2019 at 1:29 AM syzbot
[off-list ref] wrote:

quoted

syzbot has found a reproducer for 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=10d552b7200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=23e37f59d94ddd15
dashboard link: https://syzkaller.appspot.com/bug?extid=40918e4d826fb2ff9b96
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17a4c1af200000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=121b274b200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+40918e4d826fb2ff9b96@syzkaller.appspotmail.com

usb 1-1: r8712u: MAC Address from efuse = 00:e0:4c:87:00:00
usb 1-1: r8712u: Loading firmware from "rtlwifi/rtl8712u.bin"
usb 1-1: USB disconnect, device number 2
usb 1-1: Direct firmware load for rtlwifi/rtl8712u.bin failed with error -2
usb 1-1: r8712u: Firmware request failed
WARNING: CPU: 0 PID: 575 at net/core/dev.c:8152
rollback_registered_many+0x1f3/0xe70 net/core/dev.c:8152
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 575 Comm: kworker/0:4 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
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0xe8/0x16e lib/dump_stack.c:113
  panic+0x29d/0x5f2 kernel/panic.c:214
  __warn.cold+0x20/0x48 kernel/panic.c:571
  report_bug+0x262/0x2a0 lib/bug.c:186
  fixup_bug arch/x86/kernel/traps.c:179 [inline]
  fixup_bug arch/x86/kernel/traps.c:174 [inline]
  do_error_trap+0x130/0x1f0 arch/x86/kernel/traps.c:272
  do_invalid_op+0x37/0x40 arch/x86/kernel/traps.c:291
  invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:rollback_registered_many+0x1f3/0xe70 net/core/dev.c:8152
Code: 05 00 00 31 ff 44 89 fe e8 5a 15 f3 f4 45 84 ff 0f 85 49 ff ff ff e8
1c 14 f3 f4 0f 1f 44 00 00 e8 12 14 f3 f4 e8 0d 14 f3 f4 <0f> 0b 4c 89 e7
e8 33 72 f2 f6 31 ff 41 89 c4 89 c6 e8 27 15 f3 f4
RSP: 0018:ffff88809d087698 EFLAGS: 00010293
RAX: ffff88809d058000 RBX: ffff888096240000 RCX: ffffffff8c7eb146
RDX: 0000000000000000 RSI: ffffffff8c7eb163 RDI: 0000000000000001
RBP: ffff88809d0877c8 R08: ffff88809d058000 R09: fffffbfff2708111
R10: fffffbfff2708110 R11: ffffffff93840887 R12: ffff888096240070
R13: dffffc0000000000 R14: ffff88809d087758 R15: 0000000000000000
  rollback_registered+0xf7/0x1c0 net/core/dev.c:8228
  unregister_netdevice_queue net/core/dev.c:9275 [inline]
  unregister_netdevice_queue+0x1dc/0x2b0 net/core/dev.c:9268
  unregister_netdevice include/linux/netdevice.h:2655 [inline]
  unregister_netdev+0x1d/0x30 net/core/dev.c:9316
  r871xu_dev_remove+0xe7/0x223 drivers/staging/rtl8712/usb_intf.c:604
  usb_unbind_interface+0x1c9/0x980 drivers/usb/core/driver.c:423
  __device_release_driver drivers/base/dd.c:1082 [inline]
  device_release_driver_internal+0x436/0x4f0 drivers/base/dd.c:1113
  bus_remove_device+0x302/0x5c0 drivers/base/bus.c:556
  device_del+0x467/0xb90 drivers/base/core.c:2269
  usb_disable_device+0x242/0x790 drivers/usb/core/message.c:1235
  usb_disconnect+0x298/0x870 drivers/usb/core/hub.c:2197
  hub_port_connect drivers/usb/core/hub.c:4940 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
  port_event drivers/usb/core/hub.c:5350 [inline]
  hub_event+0xcd2/0x3b00 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
Kernel Offset: disabled
Rebooting in 86400 seconds..

+linux-usb mailing list

This USB bug is the most frequently triggered one right now with over
27k kernel crashes.

OK, this report is confusing. It was initially reported on the
upstream instance a long time ago, but since then has stopped
happening, as it was probably fixed. Then when we launched the USB
fuzzing instance, it has started producing similarly named reports
(with a different root cause though), and they were bucketed into this
bug by syzkaller. I've improved parsing titles of such reports in
syzkaller, so I'm invalidating this one, and syzbot should send a
properly attributed USB report soon.

#syz invalid