EXT4-fs: Ignoring removed oldalloc option
EXT4-fs: Ignoring removed orlov option
EXT4-fs (loop5): mounted filesystem without journal. Quota mode: writeback.
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:847 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0x8f4/0xaa8 fs/ext4/extents.c:962
Read of size 4 at addr ffff0000fe2b9e18 by task syz.5.910/7117

CPU: 0 PID: 7117 Comm: syz.5.910 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_binsearch fs/ext4/extents.c:847 [inline]
 ext4_find_extent+0x8f4/0xaa8 fs/ext4/extents.c:962
 ext4_ext_remove_space+0x2c0/0x3ac4 fs/ext4/extents.c:2845
 ext4_punch_hole+0x694/0xb58 fs/ext4/inode.c:4141
 ext4_fallocate+0x224/0x1abc fs/ext4/extents.c:4818
 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323
 ioctl_preallocate+0x20c/0x2b4 fs/ioctl.c:290
 file_ioctl fs/ioctl.c:-1 [inline]
 do_vfs_ioctl+0x1874/0x2100 fs/ioctl.c:849
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xe4/0x1c8 fs/ioctl.c:856
 __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:0000000029fe2a4a refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x13e2b9
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:
 ffff0000fe2b9d00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fe2b9d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000fe2b9e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff0000fe2b9e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000fe2b9f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device loop5): ext4_ext_split:1085: inode #15: comm syz.5.910: p_ext > EXT_MAX_EXTENT!