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KASAN: null-ptr-deref Read in do_journal_end

Status: upstream: reported C repro on 2025/08/05 01:55
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+c6491824ba4027804128@syzkaller.appspotmail.com
First crash: 141d, last: 6d01h
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: KASAN: null-ptr-deref Read in do_journal_end (log)
Repro: C syz .config
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/08/09 linux-6.6.y (ToT) 3a8ababb8b6a C [report] KASAN: null-ptr-deref Read in do_journal_end
2025/08/09 upstream (ToT) 37816488247d C Didn't crash
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 BUG: unable to handle kernel paging request in do_journal_end origin:upstream missing-backport 11 C done 782 18m 856d 0/3 upstream: reported C repro on 2023/08/21 09:50
upstream KASAN: null-ptr-deref Read in do_journal_end (2) fs 15 C error done 40699 716d 1243d 0/29 auto-obsoleted due to no activity on 2024/03/18 13:22
linux-5.15 KASAN: null-ptr-deref Read in do_journal_end missing-backport origin:lts-only 11 C done 673 1d13h 993d 0/3 upstream: reported C repro on 2023/04/06 14:35
upstream KASAN: null-ptr-deref Read in do_journal_end fs 11 1 1523d 1518d 0/29 auto-closed as invalid on 2022/02/20 18:03
linux-4.19 general protection fault in do_journal_end reiserfs 2 C error 3 1071d 1120d 0/1 upstream: reported C repro on 2022/11/30 04:17
linux-4.14 general protection fault in do_journal_end reiserfs 2 C 2 1047d 1084d 0/1 upstream: reported C repro on 2023/01/05 12:44
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/11/04 09:33 1h34m fix candidate upstream OK (0) job log
2025/10/26 21:50 2h04m bisect fix linux-6.6.y OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: null-ptr-deref in set_buffer_uptodate include/linux/buffer_head.h:149 [inline]
BUG: KASAN: null-ptr-deref in do_journal_end+0x10cf/0x4860 fs/reiserfs/journal.c:4086
Read of size 8 at addr 0000000000000000 by task syz-executor/5902

CPU: 1 PID: 5902 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 kasan_report+0x117/0x150 mm/kasan/report.c:581
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x288/0x290 mm/kasan/generic.c:187
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 set_buffer_uptodate include/linux/buffer_head.h:149 [inline]
 do_journal_end+0x10cf/0x4860 fs/reiserfs/journal.c:4086
 reiserfs_sync_fs+0xd0/0x150 fs/reiserfs/super.c:78
 sync_filesystem+0xea/0x220 fs/sync.c:56
 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
 kill_block_super+0x44/0x90 fs/super.c:1660
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1259
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe969d909f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd11cadb78 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000064 RCX: 00007fe969d909f7
RDX: 0000000000000200 RSI: 0000000000000009 RDI: 00007ffd11caed20
RBP: 00007fe969e11d7d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffd11caed20
R13: 00007fe969e11d7d R14: 00005555649314a8 R15: 00007ffd11cafdf0
 </TASK>
==================================================================

Crashes (35):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/10 03:14 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/10 00:55 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/09 23:49 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 08:35 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (corrupt fs)] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/12/18 22:24 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/12/16 17:31 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/12/16 10:02 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/11 16:21 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/11 02:53 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/10 22:50 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/09 17:42 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/08 10:07 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/08 10:07 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/08 10:07 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/11/08 10:07 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/19 09:34 linux-6.6.y 60a9e718726f e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/09 09:32 linux-6.6.y 355bd0b51d2f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/07 11:03 linux-6.6.y 355bd0b51d2f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/04 19:05 linux-6.6.y 355bd0b51d2f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/04 19:05 linux-6.6.y 355bd0b51d2f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/04 07:06 linux-6.6.y cc1a1c5b404a d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/04 07:06 linux-6.6.y cc1a1c5b404a d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/04 07:05 linux-6.6.y cc1a1c5b404a d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:24 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:19 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:19 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:19 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:16 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:16 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/09/01 17:16 linux-6.6.y cc1a1c5b404a 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 01:58 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 01:57 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 01:57 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 01:55 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
2025/08/05 01:55 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: null-ptr-deref Read in do_journal_end
* Struck through repros no longer work on HEAD.