kernel BUG in ext4_writepages

Status: upstream: reported C repro on 2023/03/12 17:26
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+a8068dd81edde0186829@syzkaller.appspotmail.com
First crash: 1239d, last: 7h09m
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
Re: [v6.1] kernel BUG in ext4_writepages 8 (8) 2023/08/15 16:44
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/05/06 upstream (ToT) fc4354c6e5c2 C [report] kernel BUG in ext4_do_writepages
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 kernel BUG at fs/ext4/inode.c:LINE! ext4 -1 syz, C error 145 1245d 2119d 0/1 upstream: reported C repro on 2020/10/14 01:19
android-54 kernel BUG at fs/ext4/inode.c:LINE! ext4 -1 syz, C 272 434d 2393d 0/2 upstream: reported C repro on 2020/01/14 12:13
linux-5.15 kernel BUG in ext4_writepages origin:upstream -1 syz, C error 283 17h25m 1239d 0/3 upstream: reported C repro on 2023/03/13 06:22
linux-4.14 kernel BUG at fs/ext4/inode.c:LINE! ext4 -1 syz, C 11 1253d 2047d 0/1 upstream: reported C repro on 2020/12/25 03:51
android-5-15 kernel BUG in ext4_writepages ext4 origin:upstream -1 syz, C error 703 12h34m 1384d 0/2 upstream: reported C repro on 2022/10/18 14:12
android-5-10 kernel BUG in ext4_writepages -1 syz, C error 5 1384d 1546d 2/2 fixed on 2022/11/16 18:44
android-6-1 kernel BUG in ext4_writepages origin:upstream -1 syz, C error 776 23h08m 1155d 0/2 upstream: reported C repro on 2023/06/05 07:33
upstream kernel BUG in mpage_prepare_extent_to_map ext4 -1 syz, C done error 145 1329d 1890d 0/29 auto-obsoleted due to no activity on 2024/03/07 20:46
android-5-10 kernel BUG in ext4_writepages (2) ext4 -1 syz, C error inconclusive 551 4d00h 1345d 0/2 upstream: reported C repro on 2022/11/27 00:51
▶ ▼ Fix bisection attempts (7)
Created Duration User Patch Repo Result
2026/03/17 03:32 0m bisect fix linux-6.1.y error job log
2025/11/27 05:20 2h28m bisect fix linux-6.1.y OK (0) job log log
2024/08/22 09:14 1h13m bisect fix linux-6.1.y OK (0) job log log
2024/03/28 13:38 4h12m bisect fix linux-6.1.y OK (0) job log log
2023/11/27 13:11 2h14m bisect fix linux-6.1.y OK (0) job log log
2023/10/26 11:24 2h28m bisect fix linux-6.1.y OK (0) job log log
2023/06/30 23:00 56m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/ext4/inode.c:2762!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 57 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-7:2)
RIP: 0010:ext4_writepages+0x2e5f/0x2e70 fs/ext4/inode.c:2761
Code: c1 03 38 c1 0f 8c b2 fd ff ff 4c 89 e7 e8 49 92 ac ff e9 a5 fd ff ff e8 8f 65 5b ff 0f 0b e8 88 65 5b ff 0f 0b e8 81 65 5b ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 41
RSP: 0018:ffffc90001587040 EFLAGS: 00010293
RAX: ffffffff8226c89f RBX: 000000c41000c000 RCX: ffff88801de93c00
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900015873b0 R08: ffff888054f21e6f R09: 1ffff1100a9e43cd
R10: dffffc0000000000 R11: ffffed100a9e43ce R12: dffffc0000000000
R13: 0000000000000001 R14: 0000008000000000 R15: 1ffff920002b0e34
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff1f181a000 CR3: 0000000023bbd000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491
 __writeback_single_inode+0x153/0x1170 fs/fs-writeback.c:1673
 writeback_sb_inodes+0xad5/0x17f0 fs/fs-writeback.c:1964
 wb_writeback+0x470/0xd40 fs/fs-writeback.c:2138
 wb_do_writeback fs/fs-writeback.c:2281 [inline]
 wb_workfn+0x423/0xee0 fs/fs-writeback.c:2321
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_writepages+0x2e5f/0x2e70 fs/ext4/inode.c:2761
Code: c1 03 38 c1 0f 8c b2 fd ff ff 4c 89 e7 e8 49 92 ac ff e9 a5 fd ff ff e8 8f 65 5b ff 0f 0b e8 88 65 5b ff 0f 0b e8 81 65 5b ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 41
RSP: 0018:ffffc90001587040 EFLAGS: 00010293

RAX: ffffffff8226c89f RBX: 000000c41000c000 RCX: ffff88801de93c00
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900015873b0 R08: ffff888054f21e6f R09: 1ffff1100a9e43cd
R10: dffffc0000000000 R11: ffffed100a9e43ce R12: dffffc0000000000
R13: 0000000000000001 R14: 0000008000000000 R15: 1ffff920002b0e34
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff1f1817000 CR3: 000000002e7c3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (293):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/03 06:06 linux-6.1.y fb28aa725e05 e611ffe1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/08/24 07:41 linux-6.1.y 0bc96de781b4 bf27483f .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2024/04/10 08:31 linux-6.1.y 347385861c50 171ec371 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2024/04/08 09:29 linux-6.1.y 347385861c50 ca620dd8 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2024/03/31 14:01 linux-6.1.y e5cd595e23c1 6baf5069 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/12/30 02:51 linux-6.1.y 4aa6747d9352 fb427a07 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/12/20 00:28 linux-6.1.y ba6f5fb46511 3ad490ea .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/04/01 10:27 linux-6.1.y 3b29299e5f60 f325deb0 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/04/23 23:17 linux-6.1.y 7c87defbd336 4c3406dc .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/04/04 12:20 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2025/05/29 18:41 linux-6.1.y da3c5173c55f 3d2f584d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2025/05/16 16:46 linux-6.1.y 02b72ccb5f9d cfde8269 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2025/02/02 21:30 linux-6.1.y 0cbb5f65e52f 568559e4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2023/08/18 03:52 linux-6.1.y 6c44e13dc284 74b106b6 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/08/07 05:06 linux-6.1.y 52a953d0934b 4ffcc9ef .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/03/31 14:58 linux-6.1.y 3b29299e5f60 f325deb0 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2023/03/13 06:33 linux-6.1.y 1cc3fcf63192 5205ef30 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2023/12/31 18:50 linux-6.1.y 4aa6747d9352 fb427a07 .config console log report syz [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/04/19 06:40 linux-6.1.y 7c87defbd336 303e2802 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/04/15 19:54 linux-6.1.y 8e8fc038cad5 c441f497 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/03/30 00:13 linux-6.1.y 1989cd3d56e2 b5ceaad2 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/08/03 03:39 linux-6.1.y fb28aa725e05 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/07/18 00:58 linux-6.1.y 090666d3cc90 8aaff637 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/07/12 15:19 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/07/11 14:47 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/07/11 14:46 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/05/30 19:58 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/04/16 21:00 linux-6.1.y 8e8fc038cad5 4743f87d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/04/06 04:04 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/02/15 03:30 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/02/08 20:03 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/02/08 20:03 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/02/01 08:50 linux-6.1.y cd9b81672742 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/19 14:26 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/15 09:15 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/08 18:39 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/08 05:29 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/05 06:25 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/03 06:09 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/01/01 23:11 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/30 04:36 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/27 13:21 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/26 02:19 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/25 19:55 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/25 18:35 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/21 12:15 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/17 16:55 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/12/16 04:07 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/27 03:41 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/22 09:54 linux-6.1.y 8e6e2188d949 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/21 18:50 linux-6.1.y 8e6e2188d949 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/13 09:41 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/13 04:14 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/13 01:02 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/12 22:06 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/12 09:39 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/12 06:59 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/10/11 11:55 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2025/09/22 16:26 linux-6.1.y 363a599da6d9 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
2026/07/19 02:06 linux-6.1.y 090666d3cc90 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/07/13 01:02 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/06/29 08:33 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/06/13 01:34 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/06/06 12:25 linux-6.1.y 228da13e907e cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/05/31 09:16 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/05/29 23:00 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/04/22 01:41 linux-6.1.y 7c87defbd336 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/04/04 18:02 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2026/04/04 08:06 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ext4_writepages
2023/03/12 17:25 linux-6.1.y 1cc3fcf63192 5205ef30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan kernel BUG in ext4_writepages
* Struck through repros no longer work on HEAD.