------------[ cut here ]------------
WARNING: fs/buffer.c:1183 at mark_buffer_dirty+0x299/0x400 fs/buffer.c:1183, CPU#0: syz.3.370/7489
Modules linked in:
CPU: 0 UID: 0 PID: 7489 Comm: syz.3.370 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:mark_buffer_dirty+0x299/0x400 fs/buffer.c:1183
Code: 4c 89 f7 e8 29 c4 db ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 d4 a1 fb ff e8 7f 70 75 ff eb 8c e8 78 70 75 ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 6a 70 75 ff 90 0f 0b 90 e9 cf fd ff ff
RSP: 0018:ffffc9000bb76448 EFLAGS: 00010293
RAX: ffffffff824c3088 RBX: ffff888055ff01d0 RCX: ffff88807dd43d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffff888079b58001 R08: ffff888055ff01d7 R09: 1ffff1100abfe03a
R10: dffffc0000000000 R11: ffffed100abfe03b R12: ffff88806c26b800
R13: ffff888057698570 R14: ffff888055ff01d0 R15: 0000000000000012
FS:  00007efd0ac746c0(0000) GS:ffff888125e87000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 000000002f64a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 bfs_move_block fs/bfs/file.c:44 [inline]
 bfs_move_blocks fs/bfs/file.c:57 [inline]
 bfs_get_block+0x5da/0xae0 fs/bfs/file.c:126
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin+0x8d/0x120 fs/buffer.c:2256
 bfs_write_begin+0x35/0xd0 fs/bfs/file.c:180
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
 generic_file_write_iter+0x117/0x550 mm/filemap.c:4457
 __kernel_write_iter+0x428/0x910 fs/read_write.c:619
 __kernel_write+0xef/0x150 fs/read_write.c:639
 __dump_emit+0x206/0x310 fs/coredump.c:1220
 elf_core_dump+0x2d05/0x3960 fs/binfmt_elf.c:2090
 coredump_write+0x1121/0x18b0 fs/coredump.c:1049
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200
 get_signal+0x1108/0x1340 kernel/signal.c:3019
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
 irqentry_exit+0x177/0x660 kernel/entry/common.c:196
 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7efd09d8f751
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:00000000fffffeb0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007efd09fe6090 RCX: 00007efd09d8f749
RDX: 0000000000000000 RSI: 00000000fffffeb0 RDI: 0000000002000400
RBP: 00007efd09e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007efd09fe6128 R14: 00007efd09fe6090 R15: 00007ffc173f7738
 </TASK>