[syzbot] KMSAN: uninit-value in ax88179_led_setting

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 85cfd6e539bd kmsan: core: delete kmsan_gup_pgd_range()
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=12d6c53c700000
kernel config: https://syzkaller.appspot.com/x/.config?x=b9807dd5b044fd7a
dashboard link: https://syzkaller.appspot.com/bug?extid=d3dbdf31fbe9d8f5f311
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d3dbdf...@syzkaller.appspotmail.com

ax88179_178a 2-1:0.35 (unnamed net_device) (uninitialized): Failed to read reg index 0x0001: -71
ax88179_178a 2-1:0.35 (unnamed net_device) (uninitialized): Failed to read reg index 0x0002: -71
=====================================================
BUG: KMSAN: uninit-value in ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1074 [inline]
BUG: KMSAN: uninit-value in ax88179_led_setting+0x884/0x30b0 drivers/net/usb/ax88179_178a.c:1168
ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1074 [inline]
ax88179_led_setting+0x884/0x30b0 drivers/net/usb/ax88179_178a.c:1168
ax88179_bind+0xe75/0x1990 drivers/net/usb/ax88179_178a.c:1411
usbnet_probe+0x1284/0x4140 drivers/net/usb/usbnet.c:1747
usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396
really_probe+0x67d/0x1510 drivers/base/dd.c:596
__driver_probe_device+0x3e9/0x530 drivers/base/dd.c:751
driver_probe_device drivers/base/dd.c:781 [inline]
__device_attach_driver+0x79f/0x1120 drivers/base/dd.c:898
bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427
__device_attach+0x593/0x8e0 drivers/base/dd.c:969
device_initial_probe+0x4a/0x60 drivers/base/dd.c:1016
bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487
device_add+0x1d3e/0x2400 drivers/base/core.c:3394
usb_set_configuration+0x37e9/0x3ed0 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x13c/0x300 drivers/usb/core/generic.c:238
usb_probe_device+0x309/0x570 drivers/usb/core/driver.c:293
really_probe+0x67d/0x1510 drivers/base/dd.c:596
__driver_probe_device+0x3e9/0x530 drivers/base/dd.c:751
driver_probe_device drivers/base/dd.c:781 [inline]
__device_attach_driver+0x79f/0x1120 drivers/base/dd.c:898
bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427
__device_attach+0x593/0x8e0 drivers/base/dd.c:969
device_initial_probe+0x4a/0x60 drivers/base/dd.c:1016
bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487
device_add+0x1d3e/0x2400 drivers/base/core.c:3394
usb_new_device+0x1b8e/0x2950 drivers/usb/core/hub.c:2563
hub_port_connect drivers/usb/core/hub.c:5353 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5497 [inline]
port_event drivers/usb/core/hub.c:5643 [inline]
hub_event+0x5ad2/0x8910 drivers/usb/core/hub.c:5725
process_one_work+0xdb9/0x1820 kernel/workqueue.c:2298
process_scheduled_works kernel/workqueue.c:2361 [inline]
worker_thread+0x1735/0x21f0 kernel/workqueue.c:2447
kthread+0x721/0x850 kernel/kthread.c:327
ret_from_fork+0x1f/0x30

Local variable eeprom.i created at:
ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1045 [inline]
ax88179_led_setting+0x2e2/0x30b0 drivers/net/usb/ax88179_178a.c:1168
ax88179_bind+0xe75/0x1990 drivers/net/usb/ax88179_178a.c:1411

CPU: 1 PID: 13457 Comm: kworker/1:0 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
=====================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 33d9269ef6e0 Revert "kernel: kmsan: don't instrument stack..

git tree: https://github.com/google/kmsan.git master

console output: https://syzkaller.appspot.com/x/log.txt?x=158ddbcf700000
kernel config: https://syzkaller.appspot.com/x/.config?x=d830111cc3be873

dashboard link: https://syzkaller.appspot.com/bug?extid=d3dbdf31fbe9d8f5f311
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=146e3dc3700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d3dbdf...@syzkaller.appspotmail.com

ax88179_178a 2-1:0.252 (unnamed net_device) (uninitialized): Failed to read reg index 0x0001: -71
ax88179_178a 2-1:0.252 (unnamed net_device) (uninitialized): Failed to read reg index 0x0002: -71

=====================================================
BUG: KMSAN: uninit-value in ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1074 [inline]
BUG: KMSAN: uninit-value in ax88179_led_setting+0x884/0x30b0 drivers/net/usb/ax88179_178a.c:1168
ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1074 [inline]
ax88179_led_setting+0x884/0x30b0 drivers/net/usb/ax88179_178a.c:1168

ax88179_bind+0xf00/0x1a50 drivers/net/usb/ax88179_178a.c:1412
usbnet_probe+0x1251/0x4160 drivers/net/usb/usbnet.c:1747
usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396
really_probe+0x653/0x14b0 drivers/base/dd.c:596
__driver_probe_device+0x3e9/0x530 drivers/base/dd.c:755
driver_probe_device drivers/base/dd.c:785 [inline]
__device_attach_driver+0x79f/0x1120 drivers/base/dd.c:902
bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427
__device_attach+0x593/0x8e0 drivers/base/dd.c:973
device_initial_probe+0x4a/0x60 drivers/base/dd.c:1020
bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487
device_add+0x1fff/0x26e0 drivers/base/core.c:3405

usb_set_configuration+0x37e9/0x3ed0 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x13c/0x300 drivers/usb/core/generic.c:238
usb_probe_device+0x309/0x570 drivers/usb/core/driver.c:293

really_probe+0x653/0x14b0 drivers/base/dd.c:596
__driver_probe_device+0x3e9/0x530 drivers/base/dd.c:755
driver_probe_device drivers/base/dd.c:785 [inline]
__device_attach_driver+0x79f/0x1120 drivers/base/dd.c:902
bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427
__device_attach+0x593/0x8e0 drivers/base/dd.c:973
device_initial_probe+0x4a/0x60 drivers/base/dd.c:1020
bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487
device_add+0x1fff/0x26e0 drivers/base/core.c:3405
usb_new_device+0x1b8e/0x2950 drivers/usb/core/hub.c:2566
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5660 [inline]
hub_event+0x58e3/0x89e0 drivers/usb/core/hub.c:5742
process_one_work+0xdb6/0x1820 kernel/workqueue.c:2307
worker_thread+0x10b3/0x21e0 kernel/workqueue.c:2454
kthread+0x3c7/0x500 kernel/kthread.c:377

ret_from_fork+0x1f/0x30

Local variable eeprom.i created at:
ax88179_check_eeprom drivers/net/usb/ax88179_178a.c:1045 [inline]
ax88179_led_setting+0x2e2/0x30b0 drivers/net/usb/ax88179_178a.c:1168

ax88179_bind+0xf00/0x1a50 drivers/net/usb/ax88179_178a.c:1412

CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-syzkaller #0

[David Kahurani]

On Thu, Apr 7, 2022 at 5:41 AM syzbot <syzbot+d3dbdf...@syzkaller.appspotmail.com> wrote:

syzbot has found a reproducer for the following issue on:

HEAD commit:    33d9269ef6e0 Revert "kernel: kmsan: don't instrument stack..
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=158ddbcf700000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d830111cc3be873
dashboard link: https://syzkaller.appspot.com/bug?extid=d3dbdf31fbe9d8f5f311
compiler:       clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=146e3dc3700000

Confirm whether the patch fixes it. 

#syz test https://github.com/google/kmsan.git master 

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+d3dbdf...@syzkaller.appspotmail.com

Tested on:

commit: 33d9269e Revert "kernel: kmsan: don't instrument stack..

git tree: https://github.com/google/kmsan.git master

kernel config: https://syzkaller.appspot.com/x/.config?x=d830111cc3be873
dashboard link: https://syzkaller.appspot.com/bug?extid=d3dbdf31fbe9d8f5f311
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=1130ceb7700000

Note: testing is done by a robot and is best-effort only.

[David Kahurani]

Made some changes, got to test this again just to be sure.

#syz test https://github.com/google/kmsan.git master

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+d3dbdf...@syzkaller.appspotmail.com

Tested on:

commit: 33d9269e Revert "kernel: kmsan: don't instrument stack..
git tree: https://github.com/google/kmsan.git master
kernel config: https://syzkaller.appspot.com/x/.config?x=d830111cc3be873
dashboard link: https://syzkaller.appspot.com/bug?extid=d3dbdf31fbe9d8f5f311
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=151cb868f00000

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.