syzbot


upstream boot error: BUG: unable to handle kernel paging request in get_kobj_path_length

Status: upstream: reported on 2022/08/16 08:39
Reported-by: syzbot+0c48c24994617c1e1c7a@syzkaller.appspotmail.com
First crash: 52d, last: 52d

Sample crash report:
BUG: unable to handle page fault for address: ffffffff00007c61
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD bc8f067 P4D bc8f067 PUD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 2973 Comm: udevadm Not tainted 5.19.0-syzkaller-14090-g4a9350597aff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:strlen+0x2c/0x90 lib/string.c:487
Code: 00 00 00 00 00 fc ff df 48 89 fa 55 48 89 fd 48 c1 ea 03 53 48 83 ec 08 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 48 <80> 7d 00 00 74 39 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0
RSP: 0018:ffffc90003067ad8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88801c063000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff84204670 RDI: ffffffff00007c61
RBP: ffffffff00007c61 R08: 0000000000002000 R09: 0000000000000dc0
R10: 0000000080000000 R11: 000000000008c07c R12: 0000000000000001
R13: dffffc0000000000 R14: 00000000fffffffe R15: ffff8880170c2000
FS:  00007f2a81ab9840(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff00007c61 CR3: 000000007c7ce000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __fortify_strlen include/linux/fortify-string.h:141 [inline]
 get_kobj_path_length+0x28/0x90 lib/kobject.c:109
 kobject_get_path+0x1b/0x70 lib/kobject.c:144
 kobject_uevent_env+0x254/0x1640 lib/kobject_uevent.c:529
 kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208
 uevent_store+0x42/0x90 drivers/base/bus.c:581
 drv_attr_store+0x6d/0xa0 drivers/base/bus.c:77
 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
 call_write_iter include/linux/fs.h:2192 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x9e9/0xdd0 fs/read_write.c:578
 ksys_write+0x127/0x250 fs/read_write.c:631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2a817259a3
Code: 8b 15 d9 f4 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18
RSP: 002b:00007fff9a55acc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fff9a55bf41 RCX: 00007f2a817259a3
RDX: 0000000000000003 RSI: 00007fff9a55bf41 RDI: 0000000000000003
RBP: 00005647bb783e80 R08: 0000000000000000 R09: 00007f2a817f5a60
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fff9a55acd8 R14: 0000000000000000 R15: 00005647bb1660b4
 </TASK>
Modules linked in:
CR2: ffffffff00007c61
---[ end trace 0000000000000000 ]---
RIP: 0010:strlen+0x2c/0x90 lib/string.c:487
Code: 00 00 00 00 00 fc ff df 48 89 fa 55 48 89 fd 48 c1 ea 03 53 48 83 ec 08 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 48 <80> 7d 00 00 74 39 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0
RSP: 0018:ffffc90003067ad8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88801c063000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff84204670 RDI: ffffffff00007c61
RBP: ffffffff00007c61 R08: 0000000000002000 R09: 0000000000000dc0
R10: 0000000080000000 R11: 000000000008c07c R12: 0000000000000001
R13: dffffc0000000000 R14: 00000000fffffffe R15: ffff8880170c2000
FS:  00007f2a81ab9840(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff00007c61 CR3: 000000007c7ce000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 7 bytes skipped:
   0:	df 48 89             	fisttps -0x77(%rax)
   3:	fa                   	cli
   4:	55                   	push   %rbp
   5:	48 89 fd             	mov    %rdi,%rbp
   8:	48 c1 ea 03          	shr    $0x3,%rdx
   c:	53                   	push   %rbx
   d:	48 83 ec 08          	sub    $0x8,%rsp
  11:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax
  15:	48 89 fa             	mov    %rdi,%rdx
  18:	83 e2 07             	and    $0x7,%edx
  1b:	38 d0                	cmp    %dl,%al
  1d:	7f 04                	jg     0x23
  1f:	84 c0                	test   %al,%al
  21:	75 48                	jne    0x6b
* 23:	80 7d 00 00          	cmpb   $0x0,0x0(%rbp) <-- trapping instruction
  27:	74 39                	je     0x62
  29:	48 bb 00 00 00 00 00 	movabs $0xdffffc0000000000,%rbx
  30:	fc ff df
  33:	48 89 e8             	mov    %rbp,%rax
  36:	48                   	rex.W
  37:	83                   	.byte 0x83
  38:	c0                   	.byte 0xc0

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2022/08/12 22:25 upstream 4a9350597aff 402cd70d .config log report upstream boot error: BUG: unable to handle kernel paging request in get_kobj_path_length
* Struck through repros no longer work on HEAD.