syzbot


WARNING in __folio_mark_dirty (3)

Status: upstream: reported C repro on 2025/11/20 16:41
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+b0a0670332b6b3230a0a@syzkaller.appspotmail.com
First crash: 107d, last: 23h20m
Cause bisection: failed (error log, bisect log)
  
Discussions (3)
Title Replies (including bot) Last reply
[PATCH v2] ext4: check folio uptodate state in ext4_page_mkwrite() 1 (1) 2025/11/22 01:57
[syzbot] [ext4?] WARNING in __folio_mark_dirty (3) 3 (8) 2025/11/21 19:14
[PATCH] ext4: check folio uptodate state in ext4_page_mkwrite() 3 (3) 2025/11/21 16:49
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in __folio_mark_dirty (2) gfs2 -1 C error 790989 141d 998d 29/29 fixed on 2025/07/16 19:06
upstream WARNING in __folio_mark_dirty gfs2 -1 C error 1791 1002d 1486d 22/29 fixed on 2023/02/24 13:50
linux-6.1 WARNING in __folio_mark_dirty origin:upstream missing-backport -1 C inconclusive 461847 6m 990d 0/3 upstream: reported C repro on 2023/03/08 12:14
linux-6.6 WARNING in __folio_mark_dirty origin:lts-only -1 C done 33624 8h54m 158d 0/2 upstream: reported C repro on 2025/06/16 17:15
Last patch testing requests (4)
Created Duration User Patch Repo Result
2025/11/21 12:41 21m kartikey406@gmail.com patch upstream OK log
2025/11/21 11:52 28m kartikey406@gmail.com patch upstream report log
2025/11/21 10:44 29m kartikey406@gmail.com patch upstream OK log
2025/11/21 01:34 2h10m kartikey406@gmail.com patch upstream OK log

Sample crash report:
EXT4-fs error (device loop0): ext4_ext_remove_space:2955: inode #15: comm syz.0.51: pblk 0 bad header/extent: invalid extent entries - magic f30a, entries 2, max 4(4), depth 0(0)
EXT4-fs error (device loop0) in ext4_setattr:6050: Corrupt filesystem
EXT4-fs error (device loop0): ext4_validate_block_bitmap:441: comm syz.0.51: bg 0: block 112: padding at end of block bitmap is not set
EXT4-fs error (device loop0): ext4_map_blocks:778: inode #15: block 3: comm syz.0.51: lblock 3 mapped to illegal pblock 3 (length 1)
EXT4-fs error (device loop0): ext4_ext_remove_space:2955: inode #15: comm syz.0.51: pblk 0 bad header/extent: invalid extent entries - magic f30a, entries 2, max 4(4), depth 0(0)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 6107 at mm/page-writeback.c:2716 __folio_mark_dirty+0x1fb/0xe20 mm/page-writeback.c:2716
Modules linked in:
CPU: 0 UID: 0 PID: 6107 Comm: syz.0.51 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__folio_mark_dirty+0x1fb/0xe20 mm/page-writeback.c:2716
Code: 3c 38 00 74 08 48 89 df e8 52 a7 26 00 4c 8b 33 4c 89 f6 48 83 e6 08 31 ff e8 d1 ed c4 ff 49 83 e6 08 75 1c e8 66 e8 c4 ff 90 <0f> 0b 90 eb 16 e8 5b e8 c4 ff e9 7e 07 00 00 e8 51 e8 c4 ff eb 05
RSP: 0018:ffffc90003a079d0 EFLAGS: 00010293
RAX: ffffffff81f9c4ea RBX: ffffea0001213400 RCX: ffff888025260000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff94000242681 R12: ffff8880416cb4f0
R13: ffff8880416cb4e8 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000555587ebe500(0000) GS:ffff888126df7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000440 CR3: 000000002e288000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 block_dirty_folio+0x17a/0x1d0 fs/buffer.c:754
 fault_dirty_shared_page+0x103/0x570 mm/memory.c:3519
 wp_page_shared mm/memory.c:3906 [inline]
 do_wp_page+0x263e/0x4930 mm/memory.c:4109
 handle_pte_fault mm/memory.c:6211 [inline]
 __handle_mm_fault mm/memory.c:6336 [inline]
 handle_mm_fault+0x97c/0x3400 mm/memory.c:6505
 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f385fe87398
Code: fc 89 37 c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 c5 fa 7f 07 c5 fa 7f 4c 17 f0 c3 66 0f 1f 84 00 00 00 00 00 48 8b 4c 16 f8 48 8b 36 <48> 89 37 48 89 4c 17 f8 c3 c5 fe 6f 54 16 e0 c5 fe 6f 5c 16 c0 c5
RSP: 002b:00007ffd3b8738f8 EFLAGS: 00010246
RAX: 0000200000000440 RBX: 0000000000000004 RCX: 0030656c69662f2e
RDX: 0000000000000008 RSI: 0030656c69662f2e RDI: 0000200000000440
RBP: 0000000000000000 R08: 0000001b2d820000 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000009 R12: 00007f3860115fac
R13: 00007f3860115fa0 R14: fffffffffffffffe R15: 0000000000000004
 </TASK>

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/20 16:40 upstream 23cb64fb7625 2cc4c24a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-upstream-fs WARNING in __folio_mark_dirty
2025/11/21 17:33 upstream fd95357fd8c6 280ea308 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __folio_mark_dirty
2025/11/20 14:53 upstream 23cb64fb7625 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __folio_mark_dirty
2025/11/20 14:48 upstream 23cb64fb7625 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __folio_mark_dirty
2025/11/20 14:48 upstream 23cb64fb7625 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __folio_mark_dirty
2025/11/21 00:32 upstream 8e621c9a3375 280ea308 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/11/11 23:26 upstream 24172e0d7990 4e1406b4 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/31 10:09 upstream d127176862a9 2c50b6a9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/30 05:18 upstream e53642b87a4f fd2207e7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/26 00:19 upstream 566771afc7a8 c0460fcd .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/18 11:24 upstream f406055cb18c 1c8c8cd8 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/15 04:19 upstream 9b332cece987 b6605ba8 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/11 18:23 upstream 0739473694c4 ff1712fe .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/11 02:01 upstream 917167ed1211 ff1712fe .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/10/07 23:49 upstream c746c3b51698 7e2882b3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
2025/08/06 17:39 upstream 479058002c32 4bd24a3e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __folio_mark_dirty
* Struck through repros no longer work on HEAD.