syzbot
general protection fault in bus_remove_device
Status:
premoderation: reported on 2026/08/03 04:21
Reported-by: syzbot+e9106fd19814036104d9@syzkaller.appspotmail.com
First crash: 4d12h, last: 4d12h
Sample crash report:
usb 4-1: found format II with max.bitrate = 0, frame size=4
usb 4-1: 2:1 : invalid UAC_FORMAT_TYPE desc
usb 4-1: unit 6 not found!
usb 4-1: USB disconnect, device number 14
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: 15 Comm: kworker/0:1 Not tainted 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+0x150/0x300 lib/klist.c:249
Code: 27 02 49 89 df 49 c1 ef 03 43 80 3c 27 00 74 08 48 89 df e8 e2 52 45 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 52 45 ff 49 8b 46 20 48 89 44 24 18 4c
RSP: 0018:ffffc900000f76a0 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88811349da48 RCX: 0000000000000000
RDX: ffffc900054da000 RSI: 0000000000003b42 RDI: 0000000000000020
RBP: ffffc900000f7798 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200001eec4 R12: dffffc0000000000
R13: 1ffff9200001eed8 R14: 0000000000000000 R15: 1ffff11022693b49
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd618effe81 CR3: 00000001128f0000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__device_release_driver drivers/base/dd.c:1203 [inline]
device_release_driver_internal+0x67e/0x7c0 drivers/base/dd.c:1221
device_release_driver+0x19/0x20 drivers/base/dd.c:1244
bus_remove_device+0x2df/0x340 drivers/base/bus.c:535
device_del+0x62e/0xe60 drivers/base/core.c:3453
usb_disable_device+0x3a8/0x750 drivers/usb/core/message.c:1470
usb_disconnect+0x32d/0x870 drivers/usb/core/hub.c:2310
hub_port_connect drivers/usb/core/hub.c:5338 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5639 [inline]
port_event drivers/usb/core/hub.c:5805 [inline]
hub_event+0x19c2/0x4220 drivers/usb/core/hub.c:5887
process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301
process_scheduled_works kernel/workqueue.c:2363 [inline]
worker_thread+0xd1c/0x13c0 kernel/workqueue.c:2449
kthread+0x324/0x3b0 kernel/kthread.c:313
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
Modules linked in:
---[ end trace f43d7573521779f4 ]---
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del lib/klist.c:230 [inline]
RIP: 0010:klist_remove+0x150/0x300 lib/klist.c:249
Code: 27 02 49 89 df 49 c1 ef 03 43 80 3c 27 00 74 08 48 89 df e8 e2 52 45 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 52 45 ff 49 8b 46 20 48 89 44 24 18 4c
RSP: 0018:ffffc900000f76a0 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88811349da48 RCX: 0000000000000000
RDX: ffffc900054da000 RSI: 0000000000003b42 RDI: 0000000000000020
RBP: ffffc900000f7798 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200001eec4 R12: dffffc0000000000
R13: 1ffff9200001eed8 R14: 0000000000000000 R15: 1ffff11022693b49
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200001000000 CR3: 000000000640f000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 02 49 89 add -0x77(%rcx),%cl
3: df 49 c1 fisttps -0x3f(%rcx)
6: ef out %eax,(%dx)
7: 03 43 80 add -0x80(%rbx),%eax
a: 3c 27 cmp $0x27,%al
c: 00 74 08 48 add %dh,0x48(%rax,%rcx,1)
10: 89 df mov %ebx,%edi
12: e8 e2 52 45 ff call 0xff4552f9
17: 4c 8b 33 mov (%rbx),%r14
1a: 49 83 e6 fe and $0xfffffffffffffffe,%r14
1e: 49 8d 7e 20 lea 0x20(%r14),%rdi
22: 48 89 f8 mov %rdi,%rax
25: 48 c1 e8 03 shr $0x3,%rax
* 29: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2e: 74 05 je 0x35
30: e8 c4 52 45 ff call 0xff4552f9
35: 49 8b 46 20 mov 0x20(%r14),%rax
39: 48 89 44 24 18 mov %rax,0x18(%rsp)
3e: 4c rex.WR
* Struck through repros no longer work on HEAD.