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WARNING in ext4_dirty_folio

Status: upstream: reported C repro on 2023/07/08 13:03
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+6d41dcf689b8618244d6@syzkaller.appspotmail.com
First crash: 901d, last: 4d19h
Fix commit to backport (bisect log) :
tree: upstream
commit 8ac268436e6d52f3bb4d212df9395aec97afaa00
Author: Lorenzo Stoakes <lstoakes@gmail.com>
Date: Thu May 4 21:27:52 2023 +0000

  mm/gup: disallow FOLL_LONGTERM GUP-nonfast writing to file-backed mappings

  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2025/08/19 linux-6.1.y (ToT) 0bc96de781b4 C [report] WARNING in ext4_dirty_folio
2024/03/14 upstream (ToT) fe46a7dd189e C [report] WARNING in ext4_dirty_folio
2025/08/19 upstream (ToT) be48bcf004f9 C Didn't crash
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING in ext4_dirty_folio origin:upstream -1 C 5 5d22h 94d 0/2 upstream: reported C repro on 2025/09/21 20:59
upstream WARNING in ext4_dirty_folio mm -1 C error 7440 2h40m 1370d 0/29 upstream: reported C repro on 2022/03/26 15:24
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/09/30 04:24 5h17m fix candidate upstream OK (1) job log
2023/08/17 04:55 12h10m fix candidate upstream error job log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4430 at fs/ext4/inode.c:3659 ext4_dirty_folio+0x155/0x310 fs/ext4/inode.c:3659
Modules linked in:
CPU: 0 PID: 4430 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ext4_dirty_folio+0x155/0x310 fs/ext4/inode.c:3659
Code: 49 83 3f 00 74 1f e8 1a c9 5c ff 48 8b 3c 24 48 89 de 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d e9 80 2d ca ff e8 fb c8 5c ff <0f> 0b eb dd e8 f2 c8 5c ff 0f 0b eb af e8 e9 c8 5c ff 48 89 df 48
RSP: 0018:ffffc90003537a50 EFLAGS: 00010293
RAX: ffffffff822416d5 RBX: ffffea0001a7d200 RCX: ffff88807a115940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 1ffffd400034fa40 R08: dffffc0000000000 R09: fffff9400034fa41
R10: fffff9400034fa41 R11: 1ffffd400034fa40 R12: dffffc0000000000
R13: 1ffffd400034fa41 R14: 0000000000000001 R15: ffffea0001a7d228
FS:  00007fb98b5936c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb98b592f98 CR3: 0000000079695000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 set_page_dirty_lock+0x1a/0x30 mm/page-writeback.c:2793
 fuse_copy_finish+0x104/0x200 fs/fuse/dev.c:678
 fuse_dev_do_read+0xc3d/0x11a0 fs/fuse/dev.c:1301
 fuse_dev_read+0xda/0x140 fs/fuse/dev.c:1366
 call_read_iter include/linux/fs.h:2259 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x434/0x920 fs/read_write.c:470
 ksys_read+0x143/0x240 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb98a78f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb98b593038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fb98a9e6090 RCX: 00007fb98a78f749
RDX: 0000000000002020 RSI: 0000200000000940 RDI: 0000000000000005
RBP: 00007fb98a813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb98a9e6128 R14: 00007fb98a9e6090 R15: 00007fff64ea1988
 </TASK>

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/20 20:09 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2024/03/14 18:05 linux-6.1.y 61adba85cc40 8d8ee116 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2023/09/15 18:26 linux-6.1.y 09045dae0d90 0b6a67ac .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/08 14:27 linux-6.1.y 61fd484b2cf6 668cb1fa .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/02/25 18:22 linux-6.1.y 3a8358583626 d34966d1 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/12/20 19:30 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2025/12/20 19:28 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2024/10/07 09:26 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2024/10/07 09:26 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2024/04/06 06:22 linux-6.1.y 347385861c50 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2023/10/04 14:14 linux-6.1.y d23900f974e0 b7d7ff54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2023/09/23 19:53 linux-6.1.y d23900f974e0 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_dirty_folio
2025/08/28 13:15 linux-6.1.y 0bc96de781b4 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/07/06 18:52 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/07/06 18:51 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/07/06 18:51 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/06/09 03:09 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/03/30 18:20 linux-6.1.y 8e60a714ba3b d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/03/30 18:18 linux-6.1.y 8e60a714ba3b d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2025/02/25 17:49 linux-6.1.y 3a8358583626 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2024/10/07 06:44 linux-6.1.y aa4cd140bba5 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/26 11:51 linux-6.1.y 5302e81aa209 2a509c27 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/25 18:46 linux-6.1.y 5302e81aa209 6756545c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/19 18:18 linux-6.1.y a456e1743881 022df2bb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/10 13:44 linux-6.1.y 61fd484b2cf6 d47e94ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
2023/07/08 13:03 linux-6.1.y 61fd484b2cf6 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_dirty_folio
* Struck through repros no longer work on HEAD.