syzbot
kernel BUG in register_netdevice
Status:
upstream: reported on 2026/07/30 00:10
Subsystems:
usb
Labels:
prio:low
[Documentation on labels]
Reported-by: syzbot+85ede281798faf736677@syzkaller.appspotmail.com
First crash: 9d14h, last: 2h30m
Sample crash report:
------------[ cut here ]------------
kernel BUG at net/core/dev.c:11340!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 18896 Comm: syz.5.3314 Tainted: G S L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [S]=CPU_OUT_OF_SPEC, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:register_netdevice+0x1eac/0x1ed0 net/core/dev.c:11340
Code: ff 44 89 f1 80 e1 07 38 c1 0f 8c bd fb ff ff 4c 89 f7 e8 27 4f 14 f9 e9 b0 fb ff ff e8 1d dc aa f8 90 0f 0b e8 15 dc aa f8 90 <0f> 0b e8 0d dc aa f8 90 0f 0b e8 05 dc aa f8 41 be 42 00 00 00 e9
RSP: 0018:ffffc900040475e0 EFLAGS: 00010283
RAX: ffffffff891affab RBX: 1ffff92000808ed0 RCX: 0000000000080000
RDX: ffffc90007671000 RSI: 0000000000000753 RDI: 0000000000000754
RBP: ffffc90004047758 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f5f467 R12: ffff888032f50888
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff888032f50000
FS: 00007fa1052256c0(0000) GS:ffff888125c3e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a8a663d000 CR3: 0000000050dfa000 CR4: 00000000003526f0
Call Trace:
<TASK>
register_netdev+0x40/0x60 net/core/dev.c:11562
gphonet_register_netdev drivers/usb/gadget/function/f_phonet.c:727 [inline]
pn_bind+0x115/0xb20 drivers/usb/gadget/function/f_phonet.c:511
usb_add_function+0x290/0x930 drivers/usb/gadget/composite.c:333
configfs_composite_bind+0xde0/0x1410 drivers/usb/gadget/configfs.c:1802
gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1662
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__driver_attach+0x339/0x600 drivers/base/dd.c:1292
bus_for_each_dev+0x23e/0x2c0 drivers/base/bus.c:383
bus_add_driver+0x348/0x670 drivers/base/bus.c:763
usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1752
gadget_dev_desc_UDC_store+0x1c9/0x2f0 drivers/usb/gadget/configfs.c:300
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x33a/0x430 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61e/0xbb0 fs/read_write.c:687
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa106fee019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa105225028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa107276090 RCX: 00007fa106fee019
RDX: 000000000000000c RSI: 0000200000002100 RDI: 0000000000000003
RBP: 00007fa10708500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa107276128 R14: 00007fa107276090 R15: 00007ffc951545f8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:register_netdevice+0x1eac/0x1ed0 net/core/dev.c:11340
Code: ff 44 89 f1 80 e1 07 38 c1 0f 8c bd fb ff ff 4c 89 f7 e8 27 4f 14 f9 e9 b0 fb ff ff e8 1d dc aa f8 90 0f 0b e8 15 dc aa f8 90 <0f> 0b e8 0d dc aa f8 90 0f 0b e8 05 dc aa f8 41 be 42 00 00 00 e9
RSP: 0018:ffffc900040475e0 EFLAGS: 00010283
RAX: ffffffff891affab RBX: 1ffff92000808ed0 RCX: 0000000000080000
RDX: ffffc90007671000 RSI: 0000000000000753 RDI: 0000000000000754
RBP: ffffc90004047758 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f5f467 R12: ffff888032f50888
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff888032f50000
FS: 00007fa1052256c0(0000) GS:ffff888125c3e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcc724b7e20 CR3: 0000000050dfa000 CR4: 00000000003526f0
* Struck through repros no longer work on HEAD.