syzbot


WARNING in __folio_mark_dirty (3)

Status: moderation: reported on 2025/08/10 17:42
Subsystems: mm fs
[Documentation on labels]
Reported-by: syzbot+c89af27ab247f308779b@syzkaller.appspotmail.com
First crash: 81d, last: 1d10h
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 115d 971d 29/29 fixed on 2025/07/16 19:06
upstream WARNING in __folio_mark_dirty gfs2 -1 C error 1791 975d 1459d 22/29 fixed on 2023/02/24 13:50
linux-6.1 WARNING in __folio_mark_dirty origin:upstream missing-backport -1 C inconclusive 433590 17m 963d 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 25983 now 132d 0/2 upstream: reported C repro on 2025/06/16 17:15

Sample crash report:
loop0: detected capacity change from 0 to 128
=======================================================
WARNING: The mand mount option has been deprecated and
         and is ignored by this kernel. Remove the mand
         option from the mount to silence this warning.
=======================================================
EXT4-fs (loop0): Test dummy encryption mode enabled
EXT4-fs (loop0): mounted filesystem 76b65be2-f6da-4727-8c75-0525a5b65a09 r/w without journal. Quota mode: none.
ext4 filesystem being mounted at /0/mnt supports timestamps until 2038-01-19 (0x7fffffff)
fscrypt: AES-256-XTS using implementation "xts-aes-aesni-avx"
fscrypt: AES-256-CBC-CTS using implementation "cts-cbc-aes-aesni"
loop0: detected capacity change from 128 to 64
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5321 at mm/page-writeback.c:2716 __folio_mark_dirty+0x202/0xe30 mm/page-writeback.c:2716
Modules linked in:
CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted syzkaller #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+0x202/0xe30 mm/page-writeback.c:2716
Code: 3c 20 00 74 08 48 89 df e8 7b be 2a 00 4c 8b 33 4c 89 f6 48 83 e6 08 31 ff e8 6a 84 c3 ff 49 83 e6 08 75 20 e8 7f 7f c3 ff 90 <0f> 0b 90 eb 1a e8 74 7f c3 ff 48 8b 2c 24 e9 74 07 00 00 e8 66 7f
RSP: 0018:ffffc9000d41ed90 EFLAGS: 00010093
RAX: ffffffff81fc9421 RBX: ffffea000000fdc0 RCX: ffff888000558000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8880120f97d8 R08: ffffea000000fdc7 R09: 1ffffd4000001fb8
R10: dffffc0000000000 R11: fffff94000001fb9 R12: dffffc0000000000
R13: ffff8880120f97e0 R14: 0000000000000000 R15: 0000000000000001
FS:  00007fde3e4526c0(0000) GS:ffff88808d733000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000008cc CR3: 0000000011b22000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 block_dirty_folio+0x17a/0x1d0 fs/buffer.c:754
 ext4_block_page_mkwrite fs/ext4/inode.c:6649 [inline]
 ext4_page_mkwrite+0xf07/0x1190 fs/ext4/inode.c:6746
 do_page_mkwrite+0x14d/0x310 mm/memory.c:3488
 wp_page_shared mm/memory.c:3889 [inline]
 do_wp_page+0x268d/0x5800 mm/memory.c:4108
 handle_pte_fault mm/memory.c:6193 [inline]
 __handle_mm_fault+0x1033/0x5400 mm/memory.c:6318
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6487
 do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387
 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: 0010:rep_movs_alternative+0x11/0x90 arch/x86/lib/copy_user_64.S:47
Code: e9 04 32 04 00 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 83 f9 40 73 44 83 f9 08 73 25 85 c9 74 0f 8a 06 <88> 07 48 ff c7 48 ff c6 48 ff c9 75 f1 e9 cd 31 04 00 66 2e 0f 1f
RSP: 0018:ffffc9000d41f5a8 EFLAGS: 00050202
RAX: ffffffff848b144d RBX: 0000000000000004 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffc9000d41fac0 RDI: 00002000000008cc
RBP: ffffc9000d41fb30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001a83f58 R12: 00002000000008d0
R13: 00007ffffffff000 R14: ffffc9000d41fac0 R15: 00002000000008cc
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
 _inline_copy_to_user include/linux/uaccess.h:197 [inline]
 _copy_to_user+0x8a/0xb0 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 copy_to_sockptr_offset include/linux/sockptr.h:114 [inline]
 copy_to_bpfptr_offset include/linux/bpfptr.h:65 [inline]
 bpf_check+0x131d7/0x1d720 kernel/bpf/verifier.c:24710
 bpf_prog_load+0x13ba/0x19e0 kernel/bpf/syscall.c:3077
 __sys_bpf+0x507/0x860 kernel/bpf/syscall.c:6149
 __do_sys_bpf kernel/bpf/syscall.c:6259 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6257 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6257
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde3d58efc9
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:00007fde3e452038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fde3d7e5fa0 RCX: 00007fde3d58efc9
RDX: 0000000000000094 RSI: 0000200000000840 RDI: 0000000000000005
RBP: 00007fde3d611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fde3d7e6038 R14: 00007fde3d7e5fa0 R15: 00007fffae89b978
 </TASK>
----------------
Code disassembly (best guess):
   0:	e9 04 32 04 00       	jmp    0x43209
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	cc                   	int3
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	48 83 f9 40          	cmp    $0x40,%rcx
  1d:	73 44                	jae    0x63
  1f:	83 f9 08             	cmp    $0x8,%ecx
  22:	73 25                	jae    0x49
  24:	85 c9                	test   %ecx,%ecx
  26:	74 0f                	je     0x37
  28:	8a 06                	mov    (%rsi),%al
* 2a:	88 07                	mov    %al,(%rdi) <-- trapping instruction
  2c:	48 ff c7             	inc    %rdi
  2f:	48 ff c6             	inc    %rsi
  32:	48 ff c9             	dec    %rcx
  35:	75 f1                	jne    0x28
  37:	e9 cd 31 04 00       	jmp    0x43209
  3c:	66                   	data16
  3d:	2e                   	cs
  3e:	0f                   	.byte 0xf
  3f:	1f                   	(bad)

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.