[syzbot] [usb?] KASAN: vmalloc-out-of-bounds Read in kcov_remote_stop

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fd94619c4336 Merge tag 'zonefs-6.18-rc1' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15c381e2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e2b03b8b7809165e
dashboard link: https://syzkaller.appspot.com/bug?extid=90984d3713722683112e
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/201636e25a0b/disk-fd94619c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b63e3832240c/vmlinux-fd94619c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/11fc378734e8/bzImage-fd94619c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+90984d...@syzkaller.appspotmail.com

usb 5-1: config 0 descriptor??
appletouch 5-1:0.85: Failed to read mode from device.
appletouch 5-1:0.85: probe with driver appletouch failed with error -5
usb 5-1: USB disconnect, device number 31
==================================================================
BUG: KASAN: vmalloc-out-of-bounds in __list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
Read of size 8 at addr ffffc9000ffa1008 by task kworker/1:1/44

CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
__list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
__list_add_valid include/linux/list.h:96 [inline]
__list_add include/linux/list.h:158 [inline]
list_add include/linux/list.h:177 [inline]
kcov_remote_area_put kernel/kcov.c:156 [inline]
kcov_remote_stop+0x52d/0x660 kernel/kcov.c:1060
hub_event+0x45d2/0x4a20 drivers/usb/core/hub.c:5997
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>

The buggy address belongs to a vmalloc virtual mapping
Memory state around the buggy address:
ffffc9000ffa0f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc9000ffa0f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc9000ffa1000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
^
ffffc9000ffa1080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc9000ffa1100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================


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