option from the mount to silence this warning.
=======================================================
EXT4-fs: Ignoring removed oldalloc option
EXT4-fs: Ignoring removed orlov option
EXT4-fs (loop2): mounted filesystem without journal. Quota mode: writeback.
==================================================================
BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2602 [inline]
BUG: KASAN: use-after-free in ext4_ext_remove_space+0x348b/0x40d0 fs/ext4/extents.c:2940
Read of size 4 at addr ffff88812ffbfc18 by task syz.2.17/376

CPU: 0 PID: 376 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:350
 ext4_ext_rm_leaf fs/ext4/extents.c:2602 [inline]
 ext4_ext_remove_space+0x348b/0x40d0 fs/ext4/extents.c:2940
 ext4_ext_truncate+0x200/0x320 fs/ext4/extents.c:4470
 ext4_truncate+0x9be/0xfb0 fs/ext4/inode.c:4297
 ext4_setattr+0x10f1/0x1a60 fs/ext4/inode.c:5647
 notify_change+0xcc3/0xf80 fs/attr.c:499
 do_truncate+0x1ac/0x240 fs/open.c:66
 vfs_truncate+0x26a/0x300 fs/open.c:112
 do_sys_truncate+0xf2/0x1c0 fs/open.c:135
 __do_sys_truncate fs/open.c:147 [inline]
 __se_sys_truncate fs/open.c:145 [inline]
 __x64_sys_truncate+0x5b/0x70 fs/open.c:145
 x64_sys_call+0x679/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:77
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f76eeb9acb9
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:00007ffcb09109d8 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f76eee15fa0 RCX: 00007f76eeb9acb9
RDX: 0000000000000000 RSI: 000000000000bf39 RDI: 0000200000000900
RBP: 00007f76eec08bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76eee15fac R14: 00007f76eee15fa0 R15: 00007f76eee15fa0
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0004bfefc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12ffbf
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea0004bfefc8 ffffea0004bfefc8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff88812ffbfb00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812ffbfb80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88812ffbfc00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff88812ffbfc80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812ffbfd00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================