loop0: detected capacity change from 0 to 1024
=======================================================
WARNING: The mand mount option has been deprecated and
         and is ignored by this kernel. Remove the mand
         option from the mount to silence this warning.
=======================================================
EXT4-fs: Ignoring removed oldalloc option
EXT4-fs: Ignoring removed orlov option
EXT4-fs (loop0): stripe (2) is not aligned with cluster size (16), stripe is disabled
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
netlink: 10 bytes leftover after parsing attributes in process `syz.0.0'.
==================================================================
BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2630 [inline]
BUG: KASAN: use-after-free in ext4_ext_remove_space+0x3170/0x4280 fs/ext4/extents.c:2964
Read of size 4 at addr ffff888056a97400 by task syz.0.0/5324

CPU: 0 UID: 0 PID: 5324 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 ext4_ext_rm_leaf fs/ext4/extents.c:2630 [inline]
 ext4_ext_remove_space+0x3170/0x4280 fs/ext4/extents.c:2964
 ext4_ext_truncate+0x17e/0x2f0 fs/ext4/extents.c:4537
 ext4_truncate+0xb63/0x13b0 fs/ext4/inode.c:4564
 ext4_setattr+0x106e/0x1c60 fs/ext4/inode.c:5956
 notify_change+0xc1a/0xf40 fs/attr.c:556
 do_truncate+0x1c2/0x250 fs/open.c:68
 vfs_truncate+0x4b4/0x540 fs/open.c:118
 do_sys_truncate+0xf3/0x1c0 fs/open.c:142
 __do_sys_truncate fs/open.c:154 [inline]
 __se_sys_truncate fs/open.c:152 [inline]
 __x64_sys_truncate+0x5b/0x70 fs/open.c:152
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff499d9c799
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:00007ff4961f5028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007ff49a015fa0 RCX: 00007ff499d9c799
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000200000000180
RBP: 00007ff499e32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff49a016038 R14: 00007ff49a015fa0 R15: 00007ffd65b42448
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56a97
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 ffffea00015aa608 ffffea00015aa588 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:
 ffff888056a97300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888056a97380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888056a97400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888056a97480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888056a97500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================