syzbot

------------[ cut here ]------------
kernel BUG at fs/ext4/extents.c:1015!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 429 Comm: syz.2.19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:ext4_ext_insert_index+0x54a/0x550 fs/ext4/extents.c:1015
Code: 4c 89 fa e9 ca fd ff ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c dd fd ff ff 4c 89 f7 e8 b0 fb d2 ff e9 d0 fd ff ff e8 76 cd 93 ff <0f> 0b 0f 1f 40 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 81 ec
RSP: 0018:ffffc90001796b00 EFLAGS: 00010293
RAX: ffffffff81d5ff7a RBX: ffff888132c54430 RCX: ffff8881113b93c0
RDX: 0000000000000000 RSI: 00000000fffffffd RDI: 0000000000000000
RBP: ffffc90001796b70 R08: ffff8881331b1bd7 R09: 1ffff1102663637a
R10: dffffc0000000000 R11: ffffed102663637b R12: 0000000000000000
R13: 000000000000011b R14: 00000000fffffffd R15: 0000000000000054
FS:  000055556a7de500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055934efd8fa0 CR3: 000000012fbbb000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_ext_split fs/ext4/extents.c:1275 [inline]
 ext4_ext_create_new_leaf fs/ext4/extents.c:1419 [inline]
 ext4_ext_insert_extent+0x3b09/0x47c0 fs/ext4/extents.c:2103
 ext4_ext_map_blocks+0x186c/0x61e0 fs/ext4/extents.c:4362
 ext4_map_blocks+0x988/0x1b30 fs/ext4/inode.c:674
 _ext4_get_block+0x1ea/0x540 fs/ext4/inode.c:817
 ext4_get_block_unwritten+0x2a/0x40 fs/ext4/inode.c:848
 ext4_block_write_begin+0x563/0x1160 fs/ext4/inode.c:1102
 ext4_write_begin+0x65a/0x12e0 fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x321/0xbf0 fs/ext4/inode.c:2988
 generic_perform_write+0x2b7/0x690 mm/filemap.c:3870
 ext4_buffered_write_iter+0x4ed/0x670 fs/ext4/file.c:270
 ext4_file_write_iter+0x440/0x1540 fs/ext4/file.c:-1
 call_write_iter include/linux/fs.h:2212 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x835/0xfd0 fs/read_write.c:594
 ksys_write+0x149/0x250 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:656
 x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8cc6fdff79
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:00007ffdec86f8d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8cc725afa0 RCX: 00007f8cc6fdff79
RDX: 00000000fffffdab RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007f8cc70766e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8cc725afac R14: 00007f8cc725afa0 R15: 00007f8cc725afa0
 </TASK>
Modules linked in:
---[ end trace 652596e51f7005fd ]---
RIP: 0010:ext4_ext_insert_index+0x54a/0x550 fs/ext4/extents.c:1015
Code: 4c 89 fa e9 ca fd ff ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c dd fd ff ff 4c 89 f7 e8 b0 fb d2 ff e9 d0 fd ff ff e8 76 cd 93 ff <0f> 0b 0f 1f 40 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 81 ec
RSP: 0018:ffffc90001796b00 EFLAGS: 00010293
RAX: ffffffff81d5ff7a RBX: ffff888132c54430 RCX: ffff8881113b93c0
RDX: 0000000000000000 RSI: 00000000fffffffd RDI: 0000000000000000
RBP: ffffc90001796b70 R08: ffff8881331b1bd7 R09: 1ffff1102663637a
R10: dffffc0000000000 R11: ffffed102663637b R12: 0000000000000000
R13: 000000000000011b R14: 00000000fffffffd R15: 0000000000000054
FS:  000055556a7de500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd1d1e94000 CR3: 000000012fbbb000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400