Re: [syzbot] [usb?] general protection fault in status_show

[syzbot <syzbot+83976e47ec1ef91e66f1@syzkaller.appspotmail.com>]

Hello,

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

Oops: general protection fault, probably for non-canonical address 0xdffffc000000007a: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000003d0-0x00000000000003d7]
CPU: 0 UID: 0 PID: 6619 Comm: syz.0.16 Not tainted 6.13.0-syzkaller-gbc8198dc7ebc-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:usb_hcd_is_primary_hcd+0x26/0x70 drivers/usb/core/hcd.c:2699
Code: 90 90 90 90 f3 0f 1e fa 55 53 48 89 fb e8 72 77 b0 fa 48 8d bb d0 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 3b 48 8b ab d0 03 00 00 48 85 ed 74 1c e8 43 77 b0
RSP: 0018:ffffc90003257ac0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff875ac534
RDX: 000000000000007a RSI: ffffffff86e896be RDI: 00000000000003d0
RBP: ffff888033124000 R08: 0000000000000005 R09: 0000000000000000
R10: 000000000000000f R11: 64666b636f732020 R12: 1ffff9200064af61
R13: 0000000000000000 R14: ffff88803312402d R15: 000000000000000f
FS:  00007f4de32746c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ee5ffff CR3: 000000001e2cc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 status_show_vhci drivers/usb/usbip/vhci_sysfs.c:79 [inline]
 status_show+0x2e1/0x5e0 drivers/usb/usbip/vhci_sysfs.c:162
 dev_attr_show+0x53/0xe0 drivers/base/core.c:2423
 sysfs_kf_seq_show+0x223/0x3e0 fs/sysfs/file.c:59
 seq_read_iter+0x4f4/0x12b0 fs/seq_file.c:230
 kernfs_fop_read_iter+0x414/0x580 fs/kernfs/file.c:279
 new_sync_read fs/read_write.c:484 [inline]
 vfs_read+0x886/0xbf0 fs/read_write.c:565
 ksys_read+0x12b/0x250 fs/read_write.c:708
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4de2385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4de3274038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f4de2575fa0 RCX: 00007f4de2385d29
RDX: 0000000000000062 RSI: 0000000020001080 RDI: 0000000000000003
RBP: 00007f4de2401b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4de2575fa0 R15: 00007ffe71b07568
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:usb_hcd_is_primary_hcd+0x26/0x70 drivers/usb/core/hcd.c:2699
Code: 90 90 90 90 f3 0f 1e fa 55 53 48 89 fb e8 72 77 b0 fa 48 8d bb d0 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 3b 48 8b ab d0 03 00 00 48 85 ed 74 1c e8 43 77 b0
RSP: 0018:ffffc90003257ac0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff875ac534
RDX: 000000000000007a RSI: ffffffff86e896be RDI: 00000000000003d0
RBP: ffff888033124000 R08: 0000000000000005 R09: 0000000000000000
R10: 000000000000000f R11: 64666b636f732020 R12: 1ffff9200064af61
R13: 0000000000000000 R14: ffff88803312402d R15: 000000000000000f
FS:  00007f4de32746c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5e99d20440 CR3: 000000001e2cc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	f3 0f 1e fa          	endbr64
   8:	55                   	push   %rbp
   9:	53                   	push   %rbx
   a:	48 89 fb             	mov    %rdi,%rbx
   d:	e8 72 77 b0 fa       	call   0xfab07784
  12:	48 8d bb d0 03 00 00 	lea    0x3d0(%rbx),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	75 3b                	jne    0x6b
  30:	48 8b ab d0 03 00 00 	mov    0x3d0(%rbx),%rbp
  37:	48 85 ed             	test   %rbp,%rbp
  3a:	74 1c                	je     0x58
  3c:	e8                   	.byte 0xe8
  3d:	43 77 b0             	rex.XB ja 0xfffffff0


Tested on:

commit:         bc8198dc Merge tag 'sched_ext-for-6.14' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=132315df980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=77593a73383cac88
dashboard link: https://syzkaller.appspot.com/bug?extid=83976e47ec1ef91e66f1
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1041e9f8580000