syzbot


WARNING in untrack_pfn (2)

Status: upstream: reported C repro on 2023/09/04 06:46
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+2b0bae3d3650486d7c7d@syzkaller.appspotmail.com
First crash: 295d, last: 172d
Fix commit to backport (bisect log) :
tree: upstream
commit d155df53f31068c3340733d586eb9b3ddfd70fc5
Author: Ma Wupeng <mawupeng1@huawei.com>
Date: Fri Feb 17 02:56:15 2023 +0000

  x86/mm/pat: clear VM_PAT if copy_p4d_range failed

  
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: WARNING in untrack_pfn (log)
Repro: C syz .config
  
Bug presence (2)
Date Name Commit Repro Result
2023/09/04 linux-6.1.y (ToT) c2cbfe5f5122 C [report] WARNING in untrack_pfn
2023/09/04 upstream (ToT) 708283abf896 C Didn't crash
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in untrack_pfn kernel C done error 128 92d 2164d 0/27 upstream: reported C repro on 2018/07/23 16:59
android-49 WARNING in untrack_pfn syz 35 1666d 1899d 0/3 public: reported syz repro on 2019/04/14 09:28
linux-5.15 WARNING in untrack_pfn origin:lts-only C done 7 200d 342d 0/3 upstream: reported C repro on 2023/07/19 07:05
linux-4.19 WARNING in untrack_pfn C error 24 525d 1786d 0/1 upstream: reported C repro on 2019/08/05 09:38
linux-4.14 WARNING in untrack_pfn C inconclusive 27 517d 1778d 0/1 upstream: reported C repro on 2019/08/13 08:40
android-44 WARNING in untrack_pfn C 211 1931d 2305d 0/2 closed as invalid on 2019/03/16 01:21
android-414 WARNING in untrack_pfn syz 1 2011d 1900d 0/1 public: reported syz repro on 2019/04/13 00:01
linux-6.1 WARNING in untrack_pfn 2 429d 437d 0/3 auto-obsoleted due to no activity on 2023/08/21 02:48
android-44 WARNING in untrack_pfn (2) C 71 1665d 1902d 0/2 public: reported C repro on 2019/04/11 08:44
Fix bisection attempts (3)
Created Duration User Patch Repo Result
2023/12/09 09:32 4h54m fix candidate upstream job log (1)
2023/11/17 15:10 1h04m bisect fix linux-6.1.y job log (0) log
2023/10/16 13:28 1h39m bisect fix linux-6.1.y job log (0) log

Sample crash report:
RSP: 002b:00007ffe3e0f6b78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe3e0f6b90 RCX: 00007efcf9f34b79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000a0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3e0f6b8c
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3547 at arch/x86/mm/pat/memtype.c:1107 untrack_pfn+0x30e/0x490
Modules linked in:
CPU: 0 PID: 3547 Comm: syz-executor414 Not tainted 6.1.51-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:untrack_pfn+0x30e/0x490 arch/x86/mm/pat/memtype.c:1107
Code: 8d 8c 24 a0 00 00 00 49 89 d8 e8 cd fd 8d 00 49 89 dd 89 c3 31 ff 89 c6 e8 4f 77 4b 00 85 db 0f 84 b2 00 00 00 e8 e2 73 4b 00 <0f> 0b 48 bb 00 00 00 00 00 fc ff df eb 4f 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90003aaf380 EFLAGS: 00010293
RAX: ffffffff813e941e RBX: 00000000ffffffea RCX: ffff8880293a8000
RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000000
RBP: ffffc90003aaf490 R08: ffffffff813e9411 R09: ffffffff8a7abaa5
R10: 0000000000000003 R11: ffff8880293a8000 R12: 1ffff11003d40c51
R13: ffffc90003aaf400 R14: dffffc0000000000 R15: ffff88801ea06288
FS:  000055555567a380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efcf9f67a80 CR3: 00000000727e1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 unmap_single_vma+0x1e3/0x290 mm/memory.c:1659
 unmap_vmas+0x3c4/0x560 mm/memory.c:1720
 exit_mmap+0x252/0x9f0 mm/mmap.c:3214
 __mmput+0x115/0x3c0 kernel/fork.c:1191
 mmput kernel/fork.c:1213 [inline]
 dup_mm kernel/fork.c:1548 [inline]
 copy_mm+0x1444/0x1990 kernel/fork.c:1581
 copy_process+0x19a2/0x4020 kernel/fork.c:2259
 kernel_clone+0x222/0x920 kernel/fork.c:2674
 __do_sys_clone kernel/fork.c:2815 [inline]
 __se_sys_clone kernel/fork.c:2799 [inline]
 __x64_sys_clone+0x231/0x280 kernel/fork.c:2799
 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+0x63/0xcd
RIP: 0033:0x7efcf9f34b79
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe3e0f6b78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe3e0f6b90 RCX: 00007efcf9f34b79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 00000000000000a0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3e0f6b8c
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/04 06:46 linux-6.1.y c2cbfe5f5122 696ea0d2 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in untrack_pfn
2024/01/05 19:08 linux-6.1.y 38fb82ecd144 28c42cff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in untrack_pfn
2023/11/21 04:02 linux-6.1.y 69e434a1cb21 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in untrack_pfn
2023/09/11 02:56 linux-6.1.y 59b13c2b647e 6654cf89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in untrack_pfn
* Struck through repros no longer work on HEAD.