EXT4-fs error (device loop2): mb_free_blocks:1839: group 0, inode 20: block 113:freeing already freed block (bit 7); block bitmap corrupt.
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BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2613 [inline]
BUG: KASAN: use-after-free in ext4_ext_remove_space+0x2948/0x3ac4 fs/ext4/extents.c:2951
Read of size 4 at addr ffff0000fe60ec18 by task syz-executor/4368

CPU: 0 PID: 4368 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026
Call trace:
 dump_backtrace+0x1c0/0x1ec 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+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350
 ext4_ext_rm_leaf fs/ext4/extents.c:2613 [inline]
 ext4_ext_remove_space+0x2948/0x3ac4 fs/ext4/extents.c:2951
 ext4_ext_truncate+0x134/0x1d0 fs/ext4/extents.c:4527
 ext4_truncate+0x9f4/0x1084 fs/ext4/inode.c:4291
 ext4_evict_inode+0xc10/0x1278 fs/ext4/inode.c:286
 evict+0x3e0/0x828 fs/inode.c:705
 iput_final fs/inode.c:1834 [inline]
 iput+0x754/0x7e4 fs/inode.c:1860
 do_unlinkat+0x36c/0x500 fs/namei.c:4405
 __do_sys_unlinkat fs/namei.c:4441 [inline]
 __se_sys_unlinkat fs/namei.c:4434 [inline]
 __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4434
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 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:00000000e94eeec4 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x13e60e
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:
 ffff0000fe60eb00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fe60eb80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000fe60ec00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff0000fe60ec80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fe60ed00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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EXT4-fs (loop2): unmounting filesystem.