[syzbot] KMSAN: uninit-value in kalmia_send_init_packet

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 41c66f470616 kmsan: silence -Wmissing-prototypes warnings
git tree: https://github.com/google/kmsan.git master
console+strace: https://syzkaller.appspot.com/x/log.txt?x=122f123e480000
kernel config: https://syzkaller.appspot.com/x/.config?x=a9a22da1efde3af6
dashboard link: https://syzkaller.appspot.com/bug?extid=cd80c5ef5121bfe85b55
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project.git 610139d2d9ce6746b3c617fb3e2f7886272d26ff), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=148c93e1480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=133524d1480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/69d5eef879e6/disk-41c66f47.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e91a447c44a2/vmlinux-41c66f47.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c549edb9c410/bzImage-41c66f47.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cd80c5...@syzkaller.appspotmail.com

usb 1-1: Product: syz
usb 1-1: Manufacturer: syz
usb 1-1: SerialNumber: syz
usb 1-1: config 0 descriptor??
=====================================================
BUG: KMSAN: uninit-value in kalmia_send_init_packet+0x56f/0x5f0 drivers/net/usb/kalmia.c:67
kalmia_send_init_packet+0x56f/0x5f0 drivers/net/usb/kalmia.c:67
kalmia_init_and_get_ethernet_addr drivers/net/usb/kalmia.c:113 [inline]
kalmia_bind+0x2fd/0x5a0 drivers/net/usb/kalmia.c:148
usbnet_probe+0xf8e/0x3de0 drivers/net/usb/usbnet.c:1745
usb_probe_interface+0xc4b/0x11f0 drivers/usb/core/driver.c:396
really_probe+0x506/0x1000 drivers/base/dd.c:639
__driver_probe_device+0x2fa/0x3d0 drivers/base/dd.c:778
driver_probe_device+0x72/0x7a0 drivers/base/dd.c:808
__device_attach_driver+0x548/0x8e0 drivers/base/dd.c:936
bus_for_each_drv+0x1fc/0x360 drivers/base/bus.c:427
__device_attach+0x42a/0x720 drivers/base/dd.c:1008
device_initial_probe+0x2e/0x40 drivers/base/dd.c:1057
bus_probe_device+0x13c/0x3b0 drivers/base/bus.c:487
device_add+0x1d4b/0x26c0 drivers/base/core.c:3479
usb_set_configuration+0x3157/0x3860 drivers/usb/core/message.c:2171
usb_generic_driver_probe+0x105/0x290 drivers/usb/core/generic.c:238
usb_probe_device+0x288/0x490 drivers/usb/core/driver.c:293
really_probe+0x506/0x1000 drivers/base/dd.c:639
__driver_probe_device+0x2fa/0x3d0 drivers/base/dd.c:778
driver_probe_device+0x72/0x7a0 drivers/base/dd.c:808
__device_attach_driver+0x548/0x8e0 drivers/base/dd.c:936
bus_for_each_drv+0x1fc/0x360 drivers/base/bus.c:427
__device_attach+0x42a/0x720 drivers/base/dd.c:1008
device_initial_probe+0x2e/0x40 drivers/base/dd.c:1057
bus_probe_device+0x13c/0x3b0 drivers/base/bus.c:487
device_add+0x1d4b/0x26c0 drivers/base/core.c:3479
usb_new_device+0x17ac/0x2370 drivers/usb/core/hub.c:2576
hub_port_connect drivers/usb/core/hub.c:5408 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5552 [inline]
port_event drivers/usb/core/hub.c:5712 [inline]
hub_event+0x56f3/0x7660 drivers/usb/core/hub.c:5794
process_one_work+0xb27/0x13e0 kernel/workqueue.c:2289
worker_thread+0x1076/0x1d60 kernel/workqueue.c:2436
kthread+0x31b/0x430 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Local variable act_len created at:
kalmia_send_init_packet+0x4e/0x5f0 drivers/net/usb/kalmia.c:64
kalmia_init_and_get_ethernet_addr drivers/net/usb/kalmia.c:113 [inline]
kalmia_bind+0x2fd/0x5a0 drivers/net/usb/kalmia.c:148

CPU: 1 PID: 4675 Comm: kworker/1:3 Not tainted 6.2.0-rc5-syzkaller-80200-g41c66f470616 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Workqueue: usb_hub_wq hub_event
=====================================================


---
This report 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 syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[syzbot]

> #syz test:

KMSAN bugs can only be tested on https://github.com/google/kmsan.git tree
because KMSAN tool is not upstreamed yet.
See https://goo.gl/tpsmEJ#kmsan-bugs for details.

> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> master
>

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+cd80c5...@syzkaller.appspotmail.com

Tested on:

commit: 41c66f47 kmsan: silence -Wmissing-prototypes warnings

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

console output: https://syzkaller.appspot.com/x/log.txt?x=107088be480000

kernel config: https://syzkaller.appspot.com/x/.config?x=a9a22da1efde3af6
dashboard link: https://syzkaller.appspot.com/bug?extid=cd80c5ef5121bfe85b55

compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project.git 610139d2d9ce6746b3c617fb3e2f7886272d26ff), GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=17a5cb35480000

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

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+cd80c5...@syzkaller.appspotmail.com

Tested on:

commit: 8c89ecf5 kmsan: silence -Wmissing-prototypes warnings

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

console output: https://syzkaller.appspot.com/x/log.txt?x=10d03fa3480000
kernel config: https://syzkaller.appspot.com/x/.config?x=1eb487014120d6e1
dashboard link: https://syzkaller.appspot.com/bug?extid=cd80c5ef5121bfe85b55
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=150247f3480000