syzbot


general protection fault in idr_find

Status: moderation: reported on 2024/12/21 00:01
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+15cf5e5b0032247be21d@syzkaller.appspotmail.com
First crash: 4d15h, last: 4d15h

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000050-0x0000000000000057]
CPU: 1 UID: 0 PID: 13424 Comm: syz-executor Not tainted 6.13.0-rc3-syzkaller-00017-gf44d154d6e3d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:idr_find+0x26/0x50 lib/idr.c:174
Code: 90 90 90 90 f3 0f 1e fa 55 48 89 f5 53 48 89 fb e8 2f 91 89 f6 48 8d 7b 50 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 13 8b 43 50 48 89 ee 48 89 df 5b
RSP: 0018:ffffc90003117818 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81641519
RDX: 000000000000000a RSI: ffffffff8b0fbdc1 RDI: 0000000000000050
RBP: 000000000000061d R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff888026b64980 R14: 0000000000000000 R15: 0000000010000000
FS:  000055558b867500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc77e2eec8 CR3: 000000007ad8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 find_pid_ns kernel/pid.c:320 [inline]
 find_task_by_pid_ns+0x36/0xc0 kernel/pid.c:430
 proc_pid_lookup+0xfd/0x500 fs/proc/base.c:3517
 proc_root_lookup+0x23/0x70 fs/proc/root.c:325
 __lookup_slow+0x24f/0x460 fs/namei.c:1791
 lookup_slow fs/namei.c:1808 [inline]
 walk_component+0x350/0x5b0 fs/namei.c:2112
 link_path_walk.part.0.constprop.0+0x53a/0xd40 fs/namei.c:2474
 link_path_walk fs/namei.c:2409 [inline]
 path_openat+0x228/0x2d60 fs/namei.c:3983
 do_filp_open+0x20c/0x470 fs/namei.c:4014
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1428
 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: 0033:0x7f451a384680
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44
RSP: 002b:00007ffc77e2f520 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f451a384680
RDX: 0000000000080001 RSI: 00007f451a40320c RDI: 00000000ffffff9c
RBP: 00007f451a40320c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 00007ffc77e2f5c0 R14: 00007ffc77e2fb20 R15: 00007ffc77e2fb20
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:idr_find+0x26/0x50 lib/idr.c:174
Code: 90 90 90 90 f3 0f 1e fa 55 48 89 f5 53 48 89 fb e8 2f 91 89 f6 48 8d 7b 50 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 13 8b 43 50 48 89 ee 48 89 df 5b
RSP: 0018:ffffc90003117818 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81641519
RDX: 000000000000000a RSI: ffffffff8b0fbdc1 RDI: 0000000000000050
RBP: 000000000000061d R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff888026b64980 R14: 0000000000000000 R15: 0000000010000000
FS:  000055558b867500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558b867808 CR3: 000000007ad8c000 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:	48 89 f5             	mov    %rsi,%rbp
   c:	53                   	push   %rbx
   d:	48 89 fb             	mov    %rdi,%rbx
  10:	e8 2f 91 89 f6       	call   0xf6899144
  15:	48 8d 7b 50          	lea    0x50(%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:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	74 04                	je     0x36
  32:	3c 03                	cmp    $0x3,%al
  34:	7e 13                	jle    0x49
  36:	8b 43 50             	mov    0x50(%rbx),%eax
  39:	48 89 ee             	mov    %rbp,%rsi
  3c:	48 89 df             	mov    %rbx,%rdi
  3f:	5b                   	pop    %rbx

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/16 22:12 upstream f44d154d6e3d f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in idr_find
* Struck through repros no longer work on HEAD.