[syzbot] [net?] KASAN: null-ptr-deref Read in nsim_dev_trap_report_work

[syzbot <syzbot+f9b37508c6a44a2b72b6@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    3a2cb45ca0cc net: mlxsw: i2c: Switch back to use struct i2..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=158b6207280000
kernel config:  https://syzkaller.appspot.com/x/.config?x=526f919910d4a671
dashboard link: https://syzkaller.appspot.com/bug?extid=f9b37508c6a44a2b72b6
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5fa469ebaab3/disk-3a2cb45c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e92fd67e9282/vmlinux-3a2cb45c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5201fed94bfc/bzImage-3a2cb45c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f9b37508c6a44a2b72b6@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: null-ptr-deref in netif_running include/linux/netdevice.h:3619 [inline]
BUG: KASAN: null-ptr-deref in nsim_dev_trap_report_work+0x117/0xc80 drivers/net/netdevsim/dev.c:850
Read of size 8 at addr 0000000000000038 by task kworker/1:2/29478

CPU: 1 PID: 29478 Comm: kworker/1:2 Not tainted 6.4.0-rc5-syzkaller-01182-g3a2cb45ca0cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: events nsim_dev_trap_report_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_report mm/kasan/report.c:465 [inline]
 kasan_report+0xec/0x130 mm/kasan/report.c:572
 check_region_inline mm/kasan/generic.c:181 [inline]
 kasan_check_range+0x141/0x190 mm/kasan/generic.c:187
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 netif_running include/linux/netdevice.h:3619 [inline]
 nsim_dev_trap_report_work+0x117/0xc80 drivers/net/netdevsim/dev.c:850
 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
==================================================================


---
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 syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the bug is already fixed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to change bug's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup