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EXT4-fs error (device loop4): ext4_mb_mark_diskspace_used:3358: comm syz.4.51: Allocating blocks 497-513 which overlap fs metadata
EXT4-fs (loop4): pa ffff88811b500bd0: logic 128, phys. 385, len 8
EXT4-fs error (device loop4): ext4_mb_release_inode_pa:4375: group 0, free 0, pa_free 1
------------[ cut here ]------------
kernel BUG at fs/ext4/extents.c:3184!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 626 Comm: syz.4.51 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:ext4_split_extent_at+0xe1f/0xe40 fs/ext4/extents.c:3184
Code: a7 cf d2 ff e9 05 fc ff ff 89 d9 80 e1 07 fe c1 38 c1 0f 8c 12 fc ff ff 48 89 df e8 6b cf d2 ff e9 05 fc ff ff e8 81 4f 98 ff <0f> 0b e8 7a 4f 98 ff 0f 0b e8 73 4f 98 ff 0f 0b e8 6c 4f 98 ff 0f
RSP: 0018:ffffc90001856de0 EFLAGS: 00010293
RAX: ffffffff81cc63cf RBX: 1ffff11026340a86 RCX: ffff88811ad213c0
RDX: 0000000000000000 RSI: 000000000000001f RDI: 000000000000006d
RBP: ffffc90001856f40 R08: 0000000000000010 R09: 000000004000043b
R10: dffffc0000000000 R11: ffffed1023a81eea R12: 0000000000000010
R13: 0000000000000011 R14: 000000000000000e R15: 000000000000001f
FS:  00007f26a21bf6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdab377b000 CR3: 000000011a0db000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ext4_split_extent+0x363/0x4a0 fs/ext4/extents.c:3386
 ext4_split_convert_extents fs/ext4/extents.c:3715 [inline]
 ext4_ext_handle_unwritten_extents fs/ext4/extents.c:3876 [inline]
 ext4_ext_map_blocks+0x1084/0x5dd0 fs/ext4/extents.c:4231
 ext4_map_blocks+0x985/0x1bd0 fs/ext4/inode.c:674
 mpage_map_one_extent fs/ext4/inode.c:2452 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2505 [inline]
 ext4_writepages+0x136a/0x2eb0 fs/ext4/inode.c:2873
 do_writepages+0x128/0x280 mm/page-writeback.c:2380
 __filemap_fdatawrite_range+0x2a0/0x350 mm/filemap.c:427
 file_write_and_wait_range+0x8c/0x110 mm/filemap.c:766
 ext4_sync_file+0x1a9/0x9f0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x190/0x1a0 fs/sync.c:202
 generic_write_sync include/linux/fs.h:2920 [inline]
 ext4_buffered_write_iter+0x59b/0x640 fs/ext4/file.c:278
 ext4_file_write_iter+0x53f/0x1980 fs/ext4/file.c:-1
 call_write_iter include/linux/fs.h:2066 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x758/0xdc0 fs/read_write.c:605
 ksys_pwrite64 fs/read_write.c:712 [inline]
 __do_sys_pwrite64 fs/read_write.c:722 [inline]
 __se_sys_pwrite64 fs/read_write.c:719 [inline]
 __x64_sys_pwrite64+0x197/0x220 fs/read_write.c:719
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f26a235c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f26a21bf028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f26a25d5fa0 RCX: 00007f26a235c799
RDX: 00000000200000c1 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007f26a23f2c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000009000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f26a25d6038 R14: 00007f26a25d5fa0 R15: 00007fffc720f538
Modules linked in:
---[ end trace c5c427225e85a4a5 ]---
RIP: 0010:ext4_split_extent_at+0xe1f/0xe40 fs/ext4/extents.c:3184
Code: a7 cf d2 ff e9 05 fc ff ff 89 d9 80 e1 07 fe c1 38 c1 0f 8c 12 fc ff ff 48 89 df e8 6b cf d2 ff e9 05 fc ff ff e8 81 4f 98 ff <0f> 0b e8 7a 4f 98 ff 0f 0b e8 73 4f 98 ff 0f 0b e8 6c 4f 98 ff 0f
RSP: 0018:ffffc90001856de0 EFLAGS: 00010293
RAX: ffffffff81cc63cf RBX: 1ffff11026340a86 RCX: ffff88811ad213c0
RDX: 0000000000000000 RSI: 000000000000001f RDI: 000000000000006d
RBP: ffffc90001856f40 R08: 0000000000000010 R09: 000000004000043b
R10: dffffc0000000000 R11: ffffed1023a81eea R12: 0000000000000010
R13: 0000000000000011 R14: 000000000000000e R15: 000000000000001f
FS:  00007f26a21bf6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdab377b000 CR3: 000000011a0db000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400