EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
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BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2623 [inline]
BUG: KASAN: use-after-free in ext4_ext_remove_space+0x276c/0x37c4 fs/ext4/extents.c:2961
Read of size 4 at addr ffff0000f9ccbc18 by task syz.2.133/7168

CPU: 0 UID: 0 PID: 7168 Comm: syz.2.133 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xa8/0x254 mm/kasan/report.c:408
 print_report+0x68/0x84 mm/kasan/report.c:521
 kasan_report+0xb0/0x110 mm/kasan/report.c:634
 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380
 ext4_ext_rm_leaf fs/ext4/extents.c:2623 [inline]
 ext4_ext_remove_space+0x276c/0x37c4 fs/ext4/extents.c:2961
 ext4_ext_truncate+0x134/0x1d0 fs/ext4/extents.c:4466
 ext4_truncate+0x9b8/0xfd4 fs/ext4/inode.c:4232
 ext4_truncate_failed_write fs/ext4/truncate.h:22 [inline]
 ext4_write_end+0x5e8/0x90c fs/ext4/inode.c:1347
 ext4_da_write_end+0xa0/0xa04 fs/ext4/inode.c:3079
 generic_perform_write+0x508/0x79c mm/filemap.c:4124
 ext4_buffered_write_iter+0x2b8/0x528 fs/ext4/file.c:299
 ext4_file_write_iter+0x1d8/0x1864 fs/ext4/file.c:-1
 do_iter_readv_writev+0x460/0x6a8 fs/read_write.c:-1
 vfs_writev+0x2b4/0x81c fs/read_write.c:1055
 do_pwritev fs/read_write.c:1151 [inline]
 __do_sys_pwritev2 fs/read_write.c:1209 [inline]
 __se_sys_pwritev2 fs/read_write.c:1200 [inline]
 __arm64_sys_pwritev2+0x1bc/0x2cc fs/read_write.c:1200
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xa8d pfn:0x139ccb
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffdffc3e73308 fffffdffc3e73288 0000000000000000
raw: 0000000000000a8d 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f9ccbb00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f9ccbb80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000f9ccbc00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff0000f9ccbc80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f9ccbd00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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