syzbot


general protection fault in do_rmdir

Status: upstream: reported C repro on 2023/12/08 13:26
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+119227d586c7650599dc@syzkaller.appspotmail.com
First crash: 226d, last: 6d02h
Bug presence (3)
Date Name Commit Repro Result
2023/12/04 android13-5.15-lts (ToT) 0e7c7966689d C [report] general protection fault in do_rmdir
2023/12/04 lts (merge base) 80529b4968a8 C Didn't crash
2023/12/04 upstream (ToT) 33cc938e65a9 C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in do_rmdir C 9 20d 222d 0/2 upstream: reported C repro on 2023/12/08 13:26
android-6-1 general protection fault in do_rmdir origin:downstream C done 2 41d 222d 0/2 upstream: reported C repro on 2023/12/08 13:26
Last patch testing requests (7)
Created Duration User Patch Repo Result
2024/07/11 15:52 5m retest repro android13-5.15-lts report log
2024/06/27 11:03 11m retest repro android13-5.15-lts report log
2024/05/23 07:39 2h32m retest repro android13-5.15-lts report log
2024/05/02 14:34 8m retest repro android13-5.15-lts report log
2024/04/18 07:44 1h33m retest repro android13-5.15-lts report log
2024/03/14 06:33 48m retest repro android13-5.15-lts report log
2024/02/13 23:00 13m retest repro android13-5.15-lts report log
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2024/01/04 05:56 36m bisect fix android13-5.15-lts OK (0) job log log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 1 PID: 295 Comm: syz-executor471 Not tainted 5.15.148-syzkaller-00718-g993bed180178 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:do_rmdir+0x33f/0x630 fs/namei.c:4208
Code: ff 4c 89 64 24 50 72 0d e8 6e 62 b2 ff 45 89 fc e9 99 00 00 00 49 8d 5f 30 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 e3 72 f4 ff 48 83 3b 00 74 5d e8 38
RSP: 0018:ffffc900009c7de0 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 0000000000000038 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000
RBP: ffffc900009c7f08 R08: ffffffff81c04f00 R09: ffffed102382bf82
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88811c15fbe0
R13: ffffc900009c7e60 R14: 1ffff1102382bf7c R15: 0000000000000008
FS:  00007fcb867196c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcb86719d58 CR3: 000000011e2d4000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __do_sys_rmdir fs/namei.c:4235 [inline]
 __se_sys_rmdir fs/namei.c:4233 [inline]
 __x64_sys_rmdir+0x49/0x50 fs/namei.c:4233
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fcb867783f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcb86719218 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007fcb868043f8 RCX: 00007fcb867783f9
RDX: 00007fcb86755b86 RSI: 0000000000000000 RDI: 0000000020000200
RBP: 00007fcb868043f0 R08: 00007fff8a763ee7 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcb867d101c
R13: 00007fcb867d1038 R14: 00007fff8a763e00 R15: 0030656c69662f30
 </TASK>
Modules linked in:
---[ end trace 801aba9f83302d84 ]---
RIP: 0010:do_rmdir+0x33f/0x630 fs/namei.c:4208
Code: ff 4c 89 64 24 50 72 0d e8 6e 62 b2 ff 45 89 fc e9 99 00 00 00 49 8d 5f 30 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 e3 72 f4 ff 48 83 3b 00 74 5d e8 38
RSP: 0018:ffffc900009c7de0 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 0000000000000038 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000
RBP: ffffc900009c7f08 R08: ffffffff81c04f00 R09: ffffed102382bf82
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88811c15fbe0
R13: ffffc900009c7e60 R14: 1ffff1102382bf7c R15: 0000000000000008
FS:  00007fcb867196c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556cf02d1590 CR3: 000000011e2d4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	ff 4c 89 64          	decl   0x64(%rcx,%rcx,4)
   4:	24 50                	and    $0x50,%al
   6:	72 0d                	jb     0x15
   8:	e8 6e 62 b2 ff       	call   0xffb2627b
   d:	45 89 fc             	mov    %r15d,%r12d
  10:	e9 99 00 00 00       	jmp    0xae
  15:	49 8d 5f 30          	lea    0x30(%r15),%rbx
  19:	48 89 d8             	mov    %rbx,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	48 89 df             	mov    %rbx,%rdi
  33:	e8 e3 72 f4 ff       	call   0xfff4731b
  38:	48 83 3b 00          	cmpq   $0x0,(%rbx)
  3c:	74 5d                	je     0x9b
  3e:	e8                   	.byte 0xe8
  3f:	38                   	.byte 0x38

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/04 06:32 android13-5.15-lts 993bed180178 51c4dcff .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_rmdir
2024/01/30 22:30 android13-5.15-lts 1c3a1f32bcbd 7f400fcb .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_rmdir
2023/12/04 12:59 android13-5.15-lts 0e7c7966689d f819d6f7 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_rmdir
* Struck through repros no longer work on HEAD.