[v6.6] unregister_netdevice: waiting for DEV to become free

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c2603c511feb Linux 6.6.93
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=123c2370580000
kernel config: https://syzkaller.appspot.com/x/.config?x=486bade17c8c30b9
dashboard link: https://syzkaller.appspot.com/bug?extid=009b6836b8e397538463
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5819843271d0/disk-c2603c51.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/113f268f936d/vmlinux-c2603c51.xz
kernel image: https://storage.googleapis.com/syzbot-assets/493dd7e2863f/bzImage-c2603c51.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+009b68...@syzkaller.appspotmail.com

unregister_netdevice: waiting for GPL to become free. Usage count = 2
ref_tracker: GPL@ffff88807e4d45b8 has 1/1 users at
dev_ifsioc+0xb7c/0xe20 net/core/dev_ioctl.c:589
dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786
sock_do_ioctl+0x226/0x2f0 net/socket.c:1236
sock_ioctl+0x623/0x7a0 net/socket.c:1341
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2



---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 6282921b6825 Linux 6.6.94
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16c89b70580000
kernel config: https://syzkaller.appspot.com/x/.config?x=96da6b2210cda427

dashboard link: https://syzkaller.appspot.com/bug?extid=009b6836b8e397538463
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16194f0c580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14e9d182580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bb8094930023/disk-6282921b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6b695542f7a7/vmlinux-6282921b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f899d5f4fdd2/bzImage-6282921b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+009b68...@syzkaller.appspotmail.com

unregister_netdevice: waiting for GPL to become free. Usage count = 2

ref_tracker: GPL@ffff88807c5d45b8 has 1/1 users at

dev_ifsioc+0xb7c/0xe20 net/core/dev_ioctl.c:589
dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786
sock_do_ioctl+0x226/0x2f0 net/socket.c:1236
sock_ioctl+0x623/0x7a0 net/socket.c:1341
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2



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