syzbot
general protection fault in bus_remove_device
Status:
premoderation: reported on 2026/08/10 00:03
Reported-by: syzbot+79df3d229ee536c50f62@syzkaller.appspotmail.com
First crash: 21h23m, last: 21h23m
Sample crash report:
usb 10-1: USB disconnect, device number 17
general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 0 PID: 641 Comm: kworker/0:5 Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del lib/klist.c:230 [inline]
RIP: 0010:klist_remove+0x150/0x2f0 lib/klist.c:249
Code: 44 02 49 89 df 49 c1 ef 03 43 80 3c 27 00 74 08 48 89 df e8 e2 65 39 ff 4c 8b 33 49 83 e6 fe 49 8d 7e 20 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 c4 65 39 ff 49 8b 46 20 48 89 44 24 18 4c
RSP: 0018:ffffc9000154f6a0 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88810ad06c48 RCX: 0000000000000000
RDX: ffffc9000a159000 RSI: 000000000000c4e9 RDI: 0000000000000020
RBP: ffffc9000154f798 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520002a9ec4 R12: dffffc0000000000
R13: 1ffff920002a9ed8 R14: 0000000000000000 R15: 1ffff110215a0d89
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e1abb8a008 CR3: 000000014d1e2000 CR4: 00000000003506b0
Call Trace:
<TASK>
__device_release_driver drivers/base/dd.c:1244 [inline]
device_release_driver_internal+0x683/0x7c0 drivers/base/dd.c:1262
device_release_driver+0x19/0x20 drivers/base/dd.c:1285
bus_remove_device+0x2df/0x340 drivers/base/bus.c:531
device_del+0x62e/0xe20 drivers/base/core.c:3610
usb_disable_device+0x3a8/0x750 drivers/usb/core/message.c:1472
usb_disconnect+0x32d/0x870 drivers/usb/core/hub.c:2288
hub_port_connect drivers/usb/core/hub.c:5394 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5695 [inline]
port_event drivers/usb/core/hub.c:5861 [inline]
hub_event+0x19b0/0x43f0 drivers/usb/core/hub.c:5943
process_one_work+0x6c8/0xbb0 kernel/workqueue.c:2328
process_scheduled_works kernel/workqueue.c:2391 [inline]
worker_thread+0xd4c/0x1250 kernel/workqueue.c:2477
kthread+0x3f5/0x4f0 kernel/kthread.c:337
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Modules linked in:
---[ end trace f8a35d38ad4e67b0 ]---
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del lib/klist.c:230 [inline]
RIP: 0010:klist_remove+0x150/0x2f0 lib/klist.c:249
Code: 44 02 49 89 df 49 c1 ef 03 43 80 3c 27 00 74 08 48 89 df e8 e2 65 39 ff 4c 8b 33 49 83 e6 fe 49 8d 7e 20 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 c4 65 39 ff 49 8b 46 20 48 89 44 24 18 4c
RSP: 0018:ffffc9000154f6a0 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88810ad06c48 RCX: 0000000000000000
RDX: ffffc9000a159000 RSI: 000000000000c4e9 RDI: 0000000000000020
RBP: ffffc9000154f798 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520002a9ec4 R12: dffffc0000000000
R13: 1ffff920002a9ed8 R14: 0000000000000000 R15: 1ffff110215a0d89
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f900f363c38 CR3: 000000010d631000 CR4: 00000000003506b0
----------------
Code disassembly (best guess):
0: 44 02 49 89 add -0x77(%rcx),%r9b
4: df 49 c1 fisttps -0x3f(%rcx)
7: ef out %eax,(%dx)
8: 03 43 80 add -0x80(%rbx),%eax
b: 3c 27 cmp $0x27,%al
d: 00 74 08 48 add %dh,0x48(%rax,%rcx,1)
11: 89 df mov %ebx,%edi
13: e8 e2 65 39 ff call 0xff3965fa
18: 4c 8b 33 mov (%rbx),%r14
1b: 49 83 e6 fe and $0xfffffffffffffffe,%r14
1f: 49 8d 7e 20 lea 0x20(%r14),%rdi
23: 48 89 f8 mov %rdi,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 05 je 0x36
31: e8 c4 65 39 ff call 0xff3965fa
36: 49 8b 46 20 mov 0x20(%r14),%rax
3a: 48 89 44 24 18 mov %rax,0x18(%rsp)
3f: 4c rex.WR
* Struck through repros no longer work on HEAD.