syzbot


BUG: unable to handle kernel NULL pointer dereference in put_dec

Status: closed as invalid on 2020/05/29 21:04
Subsystems: usb
[Documentation on labels]
First crash: 1485d, last: 1485d

Sample crash report:
xpad 6-1:0.65: xpad_try_sending_next_out_packet - usb_submit_urb failed with result -19
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 1aca46067 P4D 1aca46067 PUD 1acad5067 PMD 0 
Oops: 0000 [#1] SMP KASAN
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x42/0x60 kernel/kcov.c:202
Code: 34 24 74 0e 80 e6 01 74 34 80 b8 d4 12 00 00 00 74 2b 8b 90 b0 12 00 00 83 fa 02 75 20 48 8b 88 b8 12 00 00 8b 80 b4 12 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 2e
RSP: 0018:ffff8881da1df4b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000014 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff858b4d4c RDI: 0000000000000007
RBP: 0000000000000000 R08: ffff8881da196200 R09: ffffed1039ef6035
R10: ffffed1039ef6034 R11: ffff8881cf7b01a1 R12: ffff8881da1df580
R13: 0000000000000000 R14: ffff8881cf7b091c R15: ffff8881cf7b01a2
FS:  0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001aca45000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 put_dec+0x2c/0xd0 lib/vsprintf.c:263
 number+0xa24/0xb00 lib/vsprintf.c:472
 vsnprintf+0x216/0x14f0 lib/vsprintf.c:2640
 add_uevent_var+0x14d/0x310 lib/kobject_uevent.c:664
 usb_uevent+0x27e/0x490 drivers/usb/core/driver.c:899
 dev_uevent+0x1f7/0x780 drivers/base/core.c:1470
 kobject_uevent_env+0x637/0x1470 lib/kobject_uevent.c:556
 device_del+0x847/0xd30 drivers/base/core.c:2687
 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237
 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211
 hub_port_connect drivers/usb/core/hub.c:5046 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563
 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
 worker_thread+0x96/0xe20 kernel/workqueue.c:2410
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: 0000000000000000
---[ end trace 7bb82ebd87d30c66 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x42/0x60 kernel/kcov.c:202
Code: 34 24 74 0e 80 e6 01 74 34 80 b8 d4 12 00 00 00 74 2b 8b 90 b0 12 00 00 83 fa 02 75 20 48 8b 88 b8 12 00 00 8b 80 b4 12 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 2e
RSP: 0018:ffff8881da1df4b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000014 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff858b4d4c RDI: 0000000000000007
RBP: 0000000000000000 R08: ffff8881da196200 R09: ffffed1039ef6035
R10: ffffed1039ef6034 R11: ffff8881cf7b01a1 R12: ffff8881da1df580
R13: 0000000000000000 R14: ffff8881cf7b091c R15: ffff8881cf7b01a2
FS:  0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001aca45000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/03/25 22:16 https://github.com/google/kasan.git usb-fuzzer e17994d1e7b1 e8e6c7d2 .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.