Hello,
syzbot found the following crash on:
HEAD commit: eea39f24 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=16ab9982600000
kernel config: https://syzkaller.appspot.com/x/.config?x=d0c62209eedfd54e
dashboard link: https://syzkaller.appspot.com/bug?extid=058e326a87dbb54f2426
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+058e326a87dbb54f2426@xxxxxxxxxxxxxxxxxxxxxxxxx
==================================================================
BUG: KASAN: use-after-free in clear_bit
include/asm-generic/bitops-instrumented.h:56 [inline]
BUG: KASAN: use-after-free in usbhid_open+0x263/0x390
drivers/hid/usbhid/hid-core.c:727
Write of size 8 at addr ffff8881c89228c0 by task syz-executor.1/10380
CPU: 0 PID: 10380 Comm: syz-executor.1 Not tainted 5.3.0-rc5+ #28
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+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:612
check_memory_region_inline mm/kasan/generic.c:185 [inline]
check_memory_region+0x128/0x190 mm/kasan/generic.c:192
clear_bit include/asm-generic/bitops-instrumented.h:56 [inline]
usbhid_open+0x263/0x390 drivers/hid/usbhid/hid-core.c:727
hid_hw_open+0xd2/0x160 drivers/hid/hid-core.c:2023
hidraw_open+0x256/0x740 drivers/hid/hidraw.c:288
chrdev_open+0x219/0x5c0 fs/char_dev.c:414
do_dentry_open+0x494/0x1120 fs/open.c:797
do_last fs/namei.c:3416 [inline]
path_openat+0x1430/0x3f50 fs/namei.c:3533
do_filp_open+0x1a1/0x280 fs/namei.c:3563
do_sys_open+0x3c0/0x580 fs/open.c:1089
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413761
Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 19 00 00 c3 48
83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48
89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f50d4f077a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000413761
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f50d4f07850
RBP: 000000000075bf20 R08: 000000000000000f R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f50d4f086d4
R13: 00000000004c8c86 R14: 00000000004dfc10 R15: 00000000ffffffff
The buggy address belongs to the page:
page:ffffea0007224880 refcount:0 mapcount:0 mapping:0000000000000000
index:0x0
flags: 0x200000000000000()
raw: 0200000000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8881c8922780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881c8922800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881c8922880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881c8922900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881c8922980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
