Buffer I/O error on dev loop1, logical block 3245768, async page read
==================================================================
BUG: KASAN: use-after-free in sysv_new_block+0x618/0x7e4 fs/sysv/balloc.c:113
Read of size 4 at addr ffff0000dd8080c8 by task syz.1.2/4118

CPU: 1 PID: 4118 Comm: syz.1.2 Not tainted 5.15.173-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x174/0x1e4 mm/kasan/report.c:451
 __asan_report_load4_noabort+0x44/0x50 mm/kasan/report_generic.c:308
 sysv_new_block+0x618/0x7e4 fs/sysv/balloc.c:113
 alloc_branch fs/sysv/itree.c:134 [inline]
 get_block+0x258/0x1390 fs/sysv/itree.c:253
 __block_write_begin_int+0x3ec/0x1608 fs/buffer.c:2012
 __block_write_begin+0x40/0x54 fs/buffer.c:2062
 sysv_prepare_chunk+0x3c/0x50 fs/sysv/itree.c:468
 sysv_make_empty+0x98/0x4f8 fs/sysv/dir.c:257
 sysv_mkdir+0x88/0x138 fs/sysv/namei.c:130
 vfs_mkdir+0x334/0x4e4 fs/namei.c:4065
 do_mkdirat+0x20c/0x610 fs/namei.c:4090
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

The buggy address belongs to the page:
page:000000003053d884 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x11d808
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003760248 fffffc0003754bc8 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000dd807f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000dd808000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000dd808080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff0000dd808100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000dd808180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
attempt to access beyond end of device
loop1: rw=0, want=6491538, limit=128
Buffer I/O error on dev loop1, logical block 3245768, async page read
sysv_free_block: flc_count > flc_size