Hello,
syzbot has tested the proposed patch but the reproducer still triggered
crash:
WARNING in sysfs_remove_group
pvrusb2: Attached sub-driver tuner
pvrusb2: ***WARNING*** pvrusb2 driver initialization failed due to the
failure of one or more sub-device kernel modules.
pvrusb2: You need to resolve the failing condition before this driver can
function. There should be some earlier messages giving more information
about the problem.
------------[ cut here ]------------
sysfs group 'power' not found for kobject '0-0044'
WARNING: CPU: 1 PID: 586 at fs/sysfs/group.c:254 sysfs_remove_group
fs/sysfs/group.c:254 [inline]
WARNING: CPU: 1 PID: 586 at fs/sysfs/group.c:254
sysfs_remove_group+0x15a/0x1b0 fs/sysfs/group.c:245
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 586 Comm: pvrusb2-context Not tainted 5.1.0-rc3-g43151d6-dirty
#1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
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:sysfs_remove_group fs/sysfs/group.c:254 [inline]
RIP: 0010:sysfs_remove_group+0x15a/0x1b0 fs/sysfs/group.c:245
Code: 48 89 d9 49 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c
01 00 75 41 48 8b 33 48 c7 c7 a0 31 7a 8e e8 e6 c2 6e ff <0f> 0b eb 95 e8
0d de d3 ff e9 d2 fe ff ff 48 89 df e8 00 de d3 ff
RSP: 0018:ffff88809ced7b70 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffffff8f037e80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815b2132 RDI: ffffed10139daf60
RBP: 0000000000000000 R08: ffff88809ce96200 R09: ffffed1015a23edb
R10: ffffed1015a23eda R11: ffff8880ad11f6d7 R12: ffff888218b8e630
R13: ffffffff8f038520 R14: 1ffff110139daf97 R15: ffff888218b8e628
dpm_sysfs_remove+0xa2/0xc0 drivers/base/power/sysfs.c:737
device_del+0x175/0xb90 drivers/base/core.c:2246
usb 4-1: new high-speed USB device number 3 using dummy_hcd
device_unregister+0x27/0xd0 drivers/base/core.c:2301
i2c_unregister_device drivers/i2c/i2c-core-base.c:814 [inline]
__unregister_client drivers/i2c/i2c-core-base.c:1422 [inline]
__unregister_client+0x7d/0x90 drivers/i2c/i2c-core-base.c:1418
device_for_each_child+0x100/0x170 drivers/base/core.c:2401
i2c_del_adapter drivers/i2c/i2c-core-base.c:1485 [inline]
i2c_del_adapter+0x35b/0x640 drivers/i2c/i2c-core-base.c:1447
pvr2_i2c_core_done+0x6e/0xbb
drivers/media/usb/pvrusb2/pvrusb2-i2c-core.c:662
pvr2_hdw_destroy+0x17e/0x380 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2669
pvr2_context_destroy+0x89/0x240
drivers/media/usb/pvrusb2/pvrusb2-context.c:79
pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:146 [inline]
pvr2_context_thread_func+0x65e/0x870
drivers/media/usb/pvrusb2/pvrusb2-context.c:167
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..
Tested on:
commit: 43151d6c usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=15433634a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=274aad0cf966c3bc
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=13df3d24a00000
