==================================================================
BUG: KASAN: use-after-free in sysv_new_inode+0xd8c/0xf04 fs/sysv/ialloc.c:153
Read of size 2 at addr ffff0000f6ba41ce by task syz.4.986/7958

CPU: 1 PID: 7958 Comm: syz.4.986 Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:427
 kasan_report+0xd4/0x130 mm/kasan/report.c:531
 __asan_report_load2_noabort+0x2c/0x38 mm/kasan/report_generic.c:349
 sysv_new_inode+0xd8c/0xf04 fs/sysv/ialloc.c:153
 sysv_mknod+0x5c/0x100 fs/sysv/namei.c:53
 sysv_create+0x38/0x4c fs/sysv/namei.c:67
 lookup_open fs/namei.c:3482 [inline]
 open_last_lookups fs/namei.c:3550 [inline]
 path_openat+0xeac/0x2548 fs/namei.c:3780
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 file_open_name fs/open.c:1263 [inline]
 filp_open+0x1f4/0x258 fs/open.c:1283
 do_coredump+0x1b38/0x2234 fs/coredump.c:696
 get_signal+0xf74/0x1528 kernel/signal.c:2857
 do_signal arch/arm64/kernel/signal.c:1076 [inline]
 do_notify_resume+0x2f8/0x2cb8 arch/arm64/kernel/signal.c:1129
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_ia+0xe4/0x220 arch/arm64/kernel/entry-common.c:534
 el0t_64_sync_handler+0xb4/0xf0 arch/arm64/kernel/entry-common.c:661
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:00000000c8fc9212 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x136ba4
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003dae948 fffffc0003dae8c8 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f6ba4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f6ba4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000f6ba4180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff0000f6ba4200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f6ba4280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
syz.4.986: attempt to access beyond end of device
loop4: rw=2049, sector=6491536, nr_sectors = 2 limit=128
Buffer I/O error on dev loop4, logical block 3245768, lost async page write