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WARNING in inc_nlink

Status: upstream: reported C repro on 2023/03/20 05:26
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+642f43b47421d18b19dc@syzkaller.appspotmail.com
First crash: 428d, last: 3d06h
Fix commit to backport (bisect log) :
tree: upstream
commit 97f044f690bac2b094bfb7fb2d177ef946c85880
Author: Miklos Szeredi <mszeredi@redhat.com>
Date: Fri Oct 22 15:03:02 2021 +0000

  fuse: don't increment nlink in link()

  
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: WARNING in inc_nlink (log)
Repro: C syz .config
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/05/14 linux-5.15.y (ToT) b0ece631f84a C [report] WARNING in inc_nlink
2023/05/13 upstream (ToT) d4d58949a6ea C Didn't crash
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in inc_nlink (2) C error 102 541d 1296d 0/1 upstream: reported C repro on 2020/11/01 15:25
upstream WARNING in inc_nlink (2) fs C inconclusive done 21 805d 1142d 20/26 fixed on 2022/03/08 16:11
upstream WARNING in inc_nlink (3) jfs C error error 964 6h47m 795d 0/26 upstream: reported C repro on 2022/03/17 16:37
linux-6.1 WARNING in inc_nlink 81 384d 407d 0/3 auto-obsoleted due to no activity on 2023/07/31 15:23
linux-4.19 WARNING in inc_nlink C done 8 1371d 1520d 1/1 fixed on 2020/09/18 07:23
linux-4.14 WARNING in inc_nlink C done 21 1378d 1521d 1/1 fixed on 2020/09/11 09:49
linux-4.14 WARNING in inc_nlink (2) C 47 456d 1292d 0/1 upstream: reported C repro on 2020/11/06 09:55
upstream WARNING in inc_nlink C done 26 1408d 1511d 15/26 fixed on 2020/09/16 22:51
linux-6.1 WARNING in inc_nlink (2) origin:upstream C 24 2d19h 144d 0/3 upstream: reported C repro on 2023/12/28 21:17
▶ ▼ Fix bisection attempts (7)
Created Duration User Patch Repo Result
2023/12/06 06:14 4h29m fix candidate upstream job log (1)
2023/11/30 14:32 2h14m bisect fix linux-5.15.y job log (0) log
2023/10/30 05:59 1h16m bisect fix linux-5.15.y job log (0) log
2023/09/28 07:46 49m bisect fix linux-5.15.y job log (0) log
2023/07/26 19:45 1h39m bisect fix linux-5.15.y job log (0) log
2023/06/13 07:26 31m bisect fix linux-5.15.y job log (0) log
2023/04/19 09:00 34m bisect fix linux-5.15.y job log (0) log

Sample crash report:
loop0: detected capacity change from 0 to 32768
read_mapping_page failed!
ERROR: (device loop0): txCommit: 
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3499 at fs/inode.c:364 inc_nlink+0x120/0x130
Modules linked in:
CPU: 0 PID: 3499 Comm: syz-executor188 Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:inc_nlink+0x120/0x130 fs/inode.c:364
Code: ed ff e9 37 ff ff ff 44 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 49 ff ff ff 4c 89 ef e8 fa a1 ed ff e9 3c ff ff ff e8 e0 c9 a3 ff <0f> 0b eb 80 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 41 56 53 48
RSP: 0018:ffffc90002da7b28 EFLAGS: 00010293
RAX: ffffffff81dc92e0 RBX: 1ffff1100e5131b7 RCX: ffff88801aa69dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff81dc925a R09: fffffbfff1bc8c56
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff888072898db8 R14: ffff888072898d70 R15: 0000000000000007
FS:  0000555555bae380(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558d55946c78 CR3: 000000001d0df000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 jfs_mkdir+0x8e2/0xbb0 fs/jfs/namei.c:286
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4065
 do_mkdirat+0x260/0x520 fs/namei.c:4090
 __do_sys_mkdir fs/namei.c:4110 [inline]
 __se_sys_mkdir fs/namei.c:4108 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4108
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb97d892a39
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 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:00007fff465d8078 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007fb97d892a39
RDX: 00007fb97d892a39 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00007fb97d8db05e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff465d8258 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/12 02:59 linux-5.15.y 284087d4f7d5 9026e142 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan WARNING in inc_nlink
2023/05/08 08:00 linux-5.15.y 8a7f2a5c5aa1 90c93c40 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2023/03/20 05:50 linux-5.15.y 8020ae3c051d 7939252e .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/05/18 04:27 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/05/18 02:32 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/05/18 02:32 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/05/13 08:45 linux-5.15.y 284087d4f7d5 9026e142 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/04/18 02:59 linux-5.15.y c52b9710c83d acc528cb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2024/05/17 20:39 linux-5.15.y 83655231580b a12e99e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/03/20 05:26 linux-5.15.y 8020ae3c051d 7939252e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in inc_nlink
2023/05/03 05:22 linux-5.15.y 8a7f2a5c5aa1 48e0a81d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/05/02 23:35 linux-5.15.y 8a7f2a5c5aa1 48e0a81d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/05/02 16:37 linux-5.15.y 8a7f2a5c5aa1 52d40fd2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/05/02 11:29 linux-5.15.y 8a7f2a5c5aa1 52d40fd2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/05/01 10:18 linux-5.15.y 8a7f2a5c5aa1 62df2017 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/05/01 05:34 linux-5.15.y 8a7f2a5c5aa1 62df2017 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
2023/04/29 04:26 linux-5.15.y f48aeeaaa64c 62df2017 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in inc_nlink
* Struck through repros no longer work on HEAD.