EXT4-fs (loop4): mounted filesystem without journal. Quota mode: writeback.
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BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2601 [inline]
BUG: KASAN: use-after-free in ext4_ext_remove_space+0x275c/0x39c4 fs/ext4/extents.c:2939
Read of size 4 at addr ffff0000fad31c18 by task syz.4.170/4882

CPU: 1 PID: 4882 Comm: syz.4.170 Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 print_address_description+0x88/0x220 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:427
 kasan_report+0xa8/0x100 mm/kasan/report.c:531
 __asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350
 ext4_ext_rm_leaf fs/ext4/extents.c:2601 [inline]
 ext4_ext_remove_space+0x275c/0x39c4 fs/ext4/extents.c:2939
 ext4_ext_truncate+0x164/0x20c fs/ext4/extents.c:4469
 ext4_truncate+0x9dc/0x1078 fs/ext4/inode.c:4289
 ext4_setattr+0xda8/0x150c fs/ext4/inode.c:5630
 notify_change+0xb0c/0xdcc fs/attr.c:499
 do_truncate+0x178/0x1f0 fs/open.c:65
 vfs_truncate+0x23c/0x2b0 fs/open.c:111
 do_sys_truncate+0xe8/0x1b0 fs/open.c:134
 __do_sys_truncate fs/open.c:146 [inline]
 __se_sys_truncate fs/open.c:144 [inline]
 __arm64_sys_truncate+0x5c/0x70 fs/open.c:144
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:0000000067d5d6c7 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x13ad31
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000fad31b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fad31b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000fad31c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff0000fad31c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fad31d00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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