syzbot


general protection fault in khugepaged (3)

Status: moderation: reported on 2024/02/07 00:07
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+45f744a1e9371de016b0@syzkaller.appspotmail.com
First crash: 84d, last: 5d20h
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 1375d 1388d 15/26 fixed on 2020/09/16 22:51
upstream general protection fault in khugepaged (2) mm 1 151d 147d 0/26 auto-obsoleted due to no activity on 2024/01/27 04:37
linux-4.19 general protection fault in khugepaged 1 894d 894d 0/1 auto-closed as invalid on 2022/03/15 05:26

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000084: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000420-0x0000000000000427]
CPU: 1 PID: 36 Comm: khugepaged Not tainted 6.9.0-rc4-syzkaller-00266-g977b1ef51866 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2379 [inline]
RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2512 [inline]
RIP: 0010:khugepaged+0x6d4/0x1ab0 mm/khugepaged.c:2568
Code: 1f be 00 00 00 01 48 21 de 31 ff e8 d6 8b 95 ff b8 00 00 00 01 48 21 c3 0f 85 f9 0c 00 00 49 8d 7c 24 20 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 20 e9 f9 ff 4d 8b 74 24 20 49 8d 5c 24 78
RSP: 0018:ffffc90000ac7bc0 EFLAGS: 00010207
RAX: 0000000000000084 RBX: 0000000000000000 RCX: ffff88801b298000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000426
RBP: ffffc90000ac7ed0 R08: ffffffff82007a6a R09: 1ffff11002a0ecd1
R10: dffffc0000000000 R11: ffffed1002a0ecd2 R12: 0000000000000406
R13: dffffc0000000000 R14: ffff888015075f00 R15: ffff888015076688
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f778c3ded58 CR3: 000000000e134000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2379 [inline]
RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2512 [inline]
RIP: 0010:khugepaged+0x6d4/0x1ab0 mm/khugepaged.c:2568
Code: 1f be 00 00 00 01 48 21 de 31 ff e8 d6 8b 95 ff b8 00 00 00 01 48 21 c3 0f 85 f9 0c 00 00 49 8d 7c 24 20 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 05 e8 20 e9 f9 ff 4d 8b 74 24 20 49 8d 5c 24 78
RSP: 0018:ffffc90000ac7bc0 EFLAGS: 00010207
RAX: 0000000000000084 RBX: 0000000000000000 RCX: ffff88801b298000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000426
RBP: ffffc90000ac7ed0 R08: ffffffff82007a6a R09: 1ffff11002a0ecd1
R10: dffffc0000000000 R11: ffffed1002a0ecd2 R12: 0000000000000406
R13: dffffc0000000000 R14: ffff888015075f00 R15: ffff888015076688
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f628a769d58 CR3: 00000000224d6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	be 00 00 00 01       	mov    $0x1000000,%esi
   5:	48 21 de             	and    %rbx,%rsi
   8:	31 ff                	xor    %edi,%edi
   a:	e8 d6 8b 95 ff       	call   0xff958be5
   f:	b8 00 00 00 01       	mov    $0x1000000,%eax
  14:	48 21 c3             	and    %rax,%rbx
  17:	0f 85 f9 0c 00 00    	jne    0xd16
  1d:	49 8d 7c 24 20       	lea    0x20(%r12),%rdi
  22:	48 89 f8             	mov    %rdi,%rax
  25:	48 c1 e8 03          	shr    $0x3,%rax
* 29:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2e:	74 05                	je     0x35
  30:	e8 20 e9 f9 ff       	call   0xfff9e955
  35:	4d 8b 74 24 20       	mov    0x20(%r12),%r14
  3a:	49 8d 5c 24 78       	lea    0x78(%r12),%rbx

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/21 10:16 upstream 977b1ef51866 af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in khugepaged
2024/02/02 12:37 upstream 021533194476 60bf9982 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root general protection fault in khugepaged
* Struck through repros no longer work on HEAD.