syzbot

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kernel BUG at fs/ext4/inode.c:2624!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 5831 Comm: syz-executor348 Not tainted 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:ext4_do_writepages+0x3e47/0x3e50 fs/ext4/inode.c:2623
Code: c1 0f 8c 23 fd ff ff 4c 89 e7 e8 b4 cb b0 ff e9 16 fd ff ff e8 2a f8 50 ff 90 0f 0b e8 22 f8 50 ff 90 0f 0b e8 1a f8 50 ff 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000436f040 EFLAGS: 00010293
RAX: ffffffff826ef8e6 RBX: 0000006a10000000 RCX: ffff8880654bda00
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc9000436f430 R08: ffff88807cbd8057 R09: 1ffff1100f97b00a
R10: dffffc0000000000 R11: ffffed100f97b00b R12: ffffc9000436f740
R13: ffffc9000436f480 R14: 0000004000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881261f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7c498b0558 CR3: 000000000dd38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_writepages+0x203/0x350 fs/ext4/inode.c:2829
 do_writepages+0x3ae/0x7b0 mm/page-writeback.c:2656
 filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
 __filemap_fdatawrite_range mm/filemap.c:419 [inline]
 __filemap_fdatawrite mm/filemap.c:425 [inline]
 filemap_flush+0x189/0x220 mm/filemap.c:470
 ext4_release_file+0x82/0x310 fs/ext4/file.c:169
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8d6/0x2550 kernel/exit.c:953
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 get_signal+0x125e/0x1310 kernel/signal.c:3034
 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c4985d1b9
Code: Unable to access opcode bytes at 0x7f7c4985d18f.
RSP: 002b:00007f7c49811178 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f7c498e56c8 RCX: 00007f7c4985d1b9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7c498e56c8
RBP: 00007f7c498e56c0 R08: 00007f7c498116c0 R09: 00007f7c498116c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7c498e56cc
R13: 0000000000000006 R14: 00007fff86b3beb0 R15: 00007fff86b3bf98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_do_writepages+0x3e47/0x3e50 fs/ext4/inode.c:2623
Code: c1 0f 8c 23 fd ff ff 4c 89 e7 e8 b4 cb b0 ff e9 16 fd ff ff e8 2a f8 50 ff 90 0f 0b e8 22 f8 50 ff 90 0f 0b e8 1a f8 50 ff 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000436f040 EFLAGS: 00010293
RAX: ffffffff826ef8e6 RBX: 0000006a10000000 RCX: ffff8880654bda00
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc9000436f430 R08: ffff88807cbd8057 R09: 1ffff1100f97b00a
R10: dffffc0000000000 R11: ffffed100f97b00b R12: ffffc9000436f740
R13: ffffc9000436f480 R14: 0000004000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881260f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ebfd942000 CR3: 000000007f2ec000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400