syzbot


general protection fault in khugepaged (2)

Status: auto-obsoleted due to no activity on 2024/01/27 04:37
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+c1bc7ae90f42d06453b6@syzkaller.appspotmail.com
First crash: 91d, last: 91d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in khugepaged mm C done 3 1315d 1328d 15/26 fixed on 2020/09/16 22:51
linux-4.19 general protection fault in khugepaged 1 834d 834d 0/1 auto-closed as invalid on 2022/03/15 05:26
upstream general protection fault in khugepaged (3) mm 1 24d 20d 0/26 moderation: reported on 2024/02/07 00:07

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000084: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000420-0x0000000000000427]
CPU: 0 PID: 35 Comm: khugepaged Not tainted 6.7.0-rc3-next-20231128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2374 [inline]
RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2506 [inline]
RIP: 0010:khugepaged+0x7af/0x1420 mm/khugepaged.c:2562
Code: 00 89 de e8 a3 8a a2 ff 85 db 0f 84 77 0a 00 00 e8 26 8f a2 ff 49 8d 7d 20 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 3d 0b 00 00 49 8b 75 20 31 c9 31 d2 41 b8 01 00
RSP: 0018:ffffc90000abfce8 EFLAGS: 00010207
RAX: 0000000000000084 RBX: 0000000000000001 RCX: dffffc0000000000
RDX: ffff888018ab1dc0 RSI: ffffffff81e5863a RDI: 0000000000000426
RBP: 0000000020400000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000020800000
R13: 0000000000000406 R14: 0000000000000004 R15: 0000000000000846
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffeddbe6e68 CR3: 000000002161c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2374 [inline]
RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2506 [inline]
RIP: 0010:khugepaged+0x7af/0x1420 mm/khugepaged.c:2562
Code: 00 89 de e8 a3 8a a2 ff 85 db 0f 84 77 0a 00 00 e8 26 8f a2 ff 49 8d 7d 20 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 3d 0b 00 00 49 8b 75 20 31 c9 31 d2 41 b8 01 00
RSP: 0018:ffffc90000abfce8 EFLAGS: 00010207
RAX: 0000000000000084 RBX: 0000000000000001 RCX: dffffc0000000000
RDX: ffff888018ab1dc0 RSI: ffffffff81e5863a RDI: 0000000000000426
RBP: 0000000020400000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000020800000
R13: 0000000000000406 R14: 0000000000000004 R15: 0000000000000846
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2cc22000 CR3: 0000000075a59000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	89 de                	mov    %ebx,%esi
   2:	e8 a3 8a a2 ff       	call   0xffa28aaa
   7:	85 db                	test   %ebx,%ebx
   9:	0f 84 77 0a 00 00    	je     0xa86
   f:	e8 26 8f a2 ff       	call   0xffa28f3a
  14:	49 8d 7d 20          	lea    0x20(%r13),%rdi
  18:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  1f:	fc ff df
  22:	48 89 f8             	mov    %rdi,%rax
  25:	48 c1 e8 03          	shr    $0x3,%rax
* 29:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2d:	0f 85 3d 0b 00 00    	jne    0xb70
  33:	49 8b 75 20          	mov    0x20(%r13),%rsi
  37:	31 c9                	xor    %ecx,%ecx
  39:	31 d2                	xor    %edx,%edx
  3b:	41                   	rex.B
  3c:	b8                   	.byte 0xb8
  3d:	01 00                	add    %eax,(%rax)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/28 04:37 linux-next 8c87404c76c1 9fe51b7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in khugepaged
* Struck through repros no longer work on HEAD.