Re: [syzbot] [usb?] WARNING in usbnet_status_start

[syzbot <syzbot+3f89ec3d1d0842e95d50@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in usbnet_probe

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 1117 Comm: kworker/1:2 Not tainted 6.16.0-rc4-syzkaller-00311-gd1b07cc0868f-dirty #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:init_status drivers/net/usb/usbnet.c:234 [inline]
RIP: 0010:usbnet_probe+0xf4e/0x2810 drivers/net/usb/usbnet.c:1818
Code: 48 c1 ea 03 80 3c 02 00 0f 85 a2 15 00 00 49 8b 87 20 0e 00 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 02 48 89 f9 48 c1 e9 03 <0f> b6 14 11 48 89 f9 83 e1 07 38 ca 7f 08 84 d2 0f 85 f4 11 00 00
RSP: 0018:ffffc90001c2efa8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888114c4b000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8491bef0 RDI: 0000000000000002
RBP: ffffffff87c293e0 R08: 0000000000000004 R09: 00000000000005dc
R10: 00000000000005dc R11: 0000000000000001 R12: ffffffff8492f590
R13: ffff888114c4a000 R14: ffff888107be40b4 R15: ffff888107be4000
FS:  0000000000000000(0000) GS:ffff888269262000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3205ffff CR3: 000000011fb4c000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 sierra_net_probe+0x1c/0xb0 drivers/net/usb/sierra_net.c:925
 usb_probe_interface+0x303/0x9c0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x3e0 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2694
 hub_port_connect drivers/usb/core/hub.c:5566 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5866 [inline]
 hub_event+0x2f85/0x5030 drivers/usb/core/hub.c:5948
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5b3/0x6c0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:init_status drivers/net/usb/usbnet.c:234 [inline]
RIP: 0010:usbnet_probe+0xf4e/0x2810 drivers/net/usb/usbnet.c:1818
Code: 48 c1 ea 03 80 3c 02 00 0f 85 a2 15 00 00 49 8b 87 20 0e 00 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 02 48 89 f9 48 c1 e9 03 <0f> b6 14 11 48 89 f9 83 e1 07 38 ca 7f 08 84 d2 0f 85 f4 11 00 00
RSP: 0018:ffffc90001c2efa8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888114c4b000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8491bef0 RDI: 0000000000000002
RBP: ffffffff87c293e0 R08: 0000000000000004 R09: 00000000000005dc
R10: 00000000000005dc R11: 0000000000000001 R12: ffffffff8492f590
R13: ffff888114c4a000 R14: ffff888107be40b4 R15: ffff888107be4000
FS:  0000000000000000(0000) GS:ffff888269262000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3205ffff CR3: 0000000008ea4000 CR4: 00000000003506f0
----------------
Code disassembly (best guess):
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 a2 15 00 00    	jne    0x15b0
   e:	49 8b 87 20 0e 00 00 	mov    0xe20(%r15),%rax
  15:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  1c:	fc ff df
  1f:	48 8d 78 02          	lea    0x2(%rax),%rdi
  23:	48 89 f9             	mov    %rdi,%rcx
  26:	48 c1 e9 03          	shr    $0x3,%rcx
* 2a:	0f b6 14 11          	movzbl (%rcx,%rdx,1),%edx <-- trapping instruction
  2e:	48 89 f9             	mov    %rdi,%rcx
  31:	83 e1 07             	and    $0x7,%ecx
  34:	38 ca                	cmp    %cl,%dl
  36:	7f 08                	jg     0x40
  38:	84 d2                	test   %dl,%dl
  3a:	0f 85 f4 11 00 00    	jne    0x1234


Tested on:

commit:         d1b07cc0 arm64: dts: s32g: Add USB device tree informa..
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=101c3582580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=28729dff5d03ad1
dashboard link: https://syzkaller.appspot.com/bug?extid=3f89ec3d1d0842e95d50
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=141bca8c580000