Re: [syzbot] [usb?] KASAN: slab-use-after-free Read in attach_store

[syzbot <syzbot+8753715f05759f1a10de@syzkaller.appspotmail.com>]

Hello,

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

Oops: general protection fault, probably for non-canonical address 0xdffffc000000001f: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000f8-0x00000000000000ff]
CPU: 3 UID: 0 PID: 5994 Comm: syz-executor227 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x15d/0x1bd0 kernel/locking/mutex.c:821
Code: 08 84 d2 0f 85 67 14 00 00 44 8b 3d bd 29 b6 0f 45 85 ff 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 58 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 5e 14 00 00 48 3b 5b 58 0f 85 8b 07 00 00 bf 01
RSP: 0018:ffffc900034a79c0 EFLAGS: 00010202

RAX: dffffc0000000000 RBX: 00000000000000a0 RCX: 0000000000000001
RDX: 000000000000001f RSI: ffffffff8e183b4b RDI: 00000000000000f8
RBP: ffffc900034a7b30 R08: ffffffff87ea8263 R09: 0000000000000004
R10: ffffc900034a7b48 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007fa40066f6c0(0000) GS:ffff8880d60e9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555b3ccb5258 CR3: 000000002e664000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 attach_store+0x333/0x8f0 drivers/usb/usbip/vhci_sysfs.c:364
 dev_attr_store+0x58/0x80 drivers/base/core.c:2505
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa401ec7bde
Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08
RSP: 002b:00007fa40066f098 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa40066f6c0 RCX: 00007fa401ec7bde
RDX: 0000000000000009 RSI: 00007fa40066f100 RDI: 0000000000000007
RBP: 00007fa401f130b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffd0
R13: 0000000000000009 R14: 00007ffc9812f530 R15: 00007ffc9812f618
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x15d/0x1bd0 kernel/locking/mutex.c:821
Code: 08 84 d2 0f 85 67 14 00 00 44 8b 3d bd 29 b6 0f 45 85 ff 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 58 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 5e 14 00 00 48 3b 5b 58 0f 85 8b 07 00 00 bf 01
RSP: 0018:ffffc900034a79c0 EFLAGS: 00010202

RAX: dffffc0000000000 RBX: 00000000000000a0 RCX: 0000000000000001
RDX: 000000000000001f RSI: ffffffff8e183b4b RDI: 00000000000000f8
RBP: ffffc900034a7b30 R08: ffffffff87ea8263 R09: 0000000000000004
R10: ffffc900034a7b48 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007fa40066f6c0(0000) GS:ffff8880d60e9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555b3cb6c620 CR3: 000000002e664000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	08 84 d2 0f 85 67 14 	or     %al,0x1467850f(%rdx,%rdx,8)
   7:	00 00                	add    %al,(%rax)
   9:	44 8b 3d bd 29 b6 0f 	mov    0xfb629bd(%rip),%r15d        # 0xfb629cd
  10:	45 85 ff             	test   %r15d,%r15d
  13:	75 29                	jne    0x3e
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 8d 7b 58          	lea    0x58(%rbx),%rdi
  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:	0f 85 5e 14 00 00    	jne    0x1492
  34:	48 3b 5b 58          	cmp    0x58(%rbx),%rbx
  38:	0f 85 8b 07 00 00    	jne    0x7c9
  3e:	bf                   	.byte 0xbf
  3f:	01                   	.byte 0x1


Tested on:

commit:         15ef2f78 Merge tag 'input-for-v7.2-rc7' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=158bca25580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c44651ea7dd2f307
dashboard link: https://syzkaller.appspot.com/bug?extid=8753715f05759f1a10de
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17f74279580000