syzbot


usb-testing boot error: BUG: unable to handle kernel paging request in path_init

Status: upstream: reported on 2022/08/28 17:53
Reported-by: syzbot+90efd69929ca6d662ea9@syzkaller.appspotmail.com
First crash: 103d, last: 103d

Sample crash report:
BUG: unable to handle page fault for address: ffffdc0000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 100026067 P4D 100026067 PUD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 259 Comm: kworker/u4:3 Not tainted 6.0.0-rc1-syzkaller-00028-g4dce3b375179 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:path_init+0xac/0x1910 fs/namei.c:2350
Code: da 48 c1 ea 03 80 3c 02 00 0f 85 6a 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 0b 48 89 ca 48 89 4d c8 83 e1 07 48 c1 ea 03 <0f> b6 04 02 38 c8 7f 08 84 c0 0f 85 eb 13 00 00 48 8b 45 c8 31 ff
RSP: 0000:ffffc900016bf998 EFLAGS: 00010a06

RAX: dffffc0000000000 RBX: ffff88810e6b3300 RCX: 0000000000000000
RDX: 1fffe00000000000 RSI: ffffffff8183329b RDI: ffffc900016bfc50
RBP: ffffc900016bfa30 R08: 0000000000000005 R09: 0000000000200000
R10: 0000000000000040 R11: 0000000000052040 R12: ffffc900016bfb88
R13: ffffc900016bfd48 R14: 0000000000000001 R15: ffffc900016bfb88
FS:  0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffdc0000000000 CR3: 0000000007825000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 path_openat+0x183/0x28f0 fs/namei.c:3686
 do_filp_open+0x1b6/0x400 fs/namei.c:3718
 do_open_execat+0x116/0x730 fs/exec.c:919
 bprm_execve fs/exec.c:1819 [inline]
 bprm_execve+0x48c/0x1960 fs/exec.c:1806
 kernel_execve+0x3ea/0x500 fs/exec.c:2009
 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Modules linked in:
CR2: ffffdc0000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:path_init+0xac/0x1910 fs/namei.c:2350
Code: da 48 c1 ea 03 80 3c 02 00 0f 85 6a 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 0b 48 89 ca 48 89 4d c8 83 e1 07 48 c1 ea 03 <0f> b6 04 02 38 c8 7f 08 84 c0 0f 85 eb 13 00 00 48 8b 45 c8 31 ff
RSP: 0000:ffffc900016bf998 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffff88810e6b3300 RCX: 0000000000000000
RDX: 1fffe00000000000 RSI: ffffffff8183329b RDI: ffffc900016bfc50
RBP: ffffc900016bfa30 R08: 0000000000000005 R09: 0000000000200000
R10: 0000000000000040 R11: 0000000000052040 R12: ffffc900016bfb88
R13: ffffc900016bfd48 R14: 0000000000000001 R15: ffffc900016bfb88
FS:  0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffdc0000000000 CR3: 0000000007825000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 6a 15 00 00    	jne    0x1578
   e:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  15:	fc ff df
  18:	48 8b 0b             	mov    (%rbx),%rcx
  1b:	48 89 ca             	mov    %rcx,%rdx
  1e:	48 89 4d c8          	mov    %rcx,-0x38(%rbp)
  22:	83 e1 07             	and    $0x7,%ecx
  25:	48 c1 ea 03          	shr    $0x3,%rdx
* 29:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2d:	38 c8                	cmp    %cl,%al
  2f:	7f 08                	jg     0x39
  31:	84 c0                	test   %al,%al
  33:	0f 85 eb 13 00 00    	jne    0x1424
  39:	48 8b 45 c8          	mov    -0x38(%rbp),%rax
  3d:	31 ff                	xor    %edi,%edi

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-usb 2022/08/24 17:50 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 4dce3b375179 514514f6 .config log report usb-testing boot error: BUG: unable to handle kernel paging request in path_init
* Struck through repros no longer work on HEAD.