[moderation] [fs?] [mm?] WARNING in __folio_mark_dirty (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 479058002c32 Merge tag 'ata-6.17-rc1-fixes' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10404ea2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d83a2136b2ccd50c
dashboard link: https://syzkaller.appspot.com/bug?extid=c89af27ab247f308779b
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linux-...@vger.kernel.org linu...@kvack.org wi...@infradead.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-47905800.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1e8891d11ad7/vmlinux-47905800.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4f7fce0b23bb/bzImage-47905800.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c89af2...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 2048
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
ext4 filesystem being mounted at /0/file0 supports timestamps until 2038-01-19 (0x7fffffff)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5370 at mm/page-writeback.c:2740 __folio_mark_dirty+0x100/0xec0 mm/page-writeback.c:2740
Modules linked in:
CPU: 0 UID: 0 PID: 5370 Comm: syz.0.0 Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__folio_mark_dirty+0x100/0xec0 mm/page-writeback.c:2740
Code: 3c 08 00 74 08 48 89 df e8 6d b9 29 00 4c 8b 33 4c 89 f6 48 83 e6 08 31 ff e8 0c d5 c4 ff 49 83 e6 08 75 20 e8 21 d0 c4 ff 90 <0f> 0b 90 eb 1a e8 16 d0 c4 ff e9 bb 08 00 00 e8 0c d0 c4 ff 48 8b
RSP: 0018:ffffc9000d3e7a40 EFLAGS: 00010083
RAX: ffffffff81faeb3f RBX: ffffea000134bb40 RCX: 0000000000100000
RDX: ffffc9000e132000 RSI: 00000000000bbf45 RDI: 00000000000bbf46
RBP: 0000000000000001 R08: ffffea000134bb47 R09: 1ffffd4000269768
R10: dffffc0000000000 R11: fffff94000269769 R12: 0000000000000a02
R13: ffff8880433da168 R14: 0000000000000000 R15: ffff8880433da170
FS: 00007fe7ed5ed6c0(0000) GS:ffff88808d218000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555799b37c8 CR3: 000000003f192000 CR4: 0000000000352ef0
Call Trace:
<TASK>
block_dirty_folio+0x17a/0x1d0 fs/buffer.c:754
unpin_user_pages_dirty_lock+0x37d/0x510 mm/gup.c:326
process_vm_rw_single_vec mm/process_vm_access.c:127 [inline]
process_vm_rw_core mm/process_vm_access.c:216 [inline]
process_vm_rw+0x841/0xaf0 mm/process_vm_access.c:284
__do_sys_process_vm_writev mm/process_vm_access.c:304 [inline]
__se_sys_process_vm_writev mm/process_vm_access.c:299 [inline]
__x64_sys_process_vm_writev+0xe0/0x100 mm/process_vm_access.c:299
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe7f118ebe9
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:00007fe7ed5ed038 EFLAGS: 00000246 ORIG_RAX: 0000000000000137
RAX: ffffffffffffffda RBX: 00007fe7f13b5fa0 RCX: 00007fe7f118ebe9
RDX: 0000000000000001 RSI: 0000200000c22000 RDI: 0000000000000004
RBP: 00007fe7f1211e19 R08: 0000000000000001 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe7f13b6038 R14: 00007fe7f13b5fa0 R15: 00007ffef413ea78
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 23cb64fb7625 Merge tag 'soc-fixes-6.18-3' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1287997c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=38a0c4cddc846161
dashboard link: https://syzkaller.appspot.com/bug?extid=c89af27ab247f308779b
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=172cd658580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15378484580000
CC: [ak...@linux-foundation.org linux...@vger.kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org linu...@kvack.org wi...@infradead.org]

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a14ebce6c664/disk-23cb64fb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7703c3032e2f/vmlinux-23cb64fb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a16c5b94924d/bzImage-23cb64fb.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4fa9525269b6/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=11d42a12580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c89af2...@syzkaller.appspotmail.com

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>


---
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[syzbot]

Sending this report to the next reporting stage.