loop0: rw=0, sector=6491536, nr_sectors = 2 limit=128
Buffer I/O error on dev loop0, logical block 3245768, async page read
==================================================================
BUG: KASAN: use-after-free in sysv_new_inode+0xda8/0xf20 fs/sysv/ialloc.c:153
Read of size 2 at addr ffff0000f27fc1ce by task syz.0.462/7783

CPU: 1 PID: 7783 Comm: syz.0.462 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_load2_noabort+0x2c/0x38 mm/kasan/report_generic.c:349
 sysv_new_inode+0xda8/0xf20 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:3490 [inline]
 open_last_lookups fs/namei.c:3558 [inline]
 path_openat+0xe18/0x26bc fs/namei.c:3788
 do_filp_open+0x194/0x384 fs/namei.c:3818
 do_sys_openat2+0x134/0x3f4 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __arm64_sys_openat+0x118/0x14c fs/open.c:1347
 __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

Allocated by task 7134:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x430 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x22c/0x308 mm/slub.c:3383
 __sigqueue_alloc+0x3e0/0x4e0 kernel/signal.c:436
 __send_signal_locked+0x1d8/0xc78 kernel/signal.c:1129
 send_signal_locked+0xac/0x850 kernel/signal.c:1258
 force_sig_info_to_task+0x2b0/0x384 kernel/signal.c:1354
 force_sig_fault_to_task kernel/signal.c:1725 [inline]
 force_sig_fault+0xbc/0x114 kernel/signal.c:1731
 arm64_force_sig_fault+0x6c/0x80 arch/arm64/kernel/traps.c:272
 do_page_fault+0x7c4/0x98c arch/arm64/mm/fault.c:-1
 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:804
 el0_da+0x70/0x144 arch/arm64/kernel/entry-common.c:515
 el0t_64_sync_handler+0x90/0xf0 arch/arm64/kernel/entry-common.c:658
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000f27fc1c0
 which belongs to the cache sigqueue of size 80
The buggy address is located 14 bytes inside of
 80-byte region [ffff0000f27fc1c0, ffff0000f27fc210)

The buggy address belongs to the physical page:
page:00000000480357eb refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000f27fcf50 pfn:0x1327fc
memcg:ffff0000f1cf5001
flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000200 fffffc00032c8708 fffffc0003b5e108 ffff0000c03dd080
raw: ffff0000f27fcf50 0000000000240000 00000001ffffffff ffff0000f1cf5001
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f27fc080: fb fb fb fb fb fb fb fb fc fc fc fc fb fb fb fb
 ffff0000f27fc100: fb fb fb fb fb fb fc fc fc fc fb fb fb fb fb fb
>ffff0000f27fc180: fb fb fb fb fc fc fc fc fb fb fb fb fb fb fb fb
                                              ^
 ffff0000f27fc200: fb fb fc fc fc fc fb fb fb fb fb fb fb fb fb fb
 ffff0000f27fc280: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fc fc
==================================================================
unable to read i-node block
syz.0.462: attempt to access beyond end of device
loop0: rw=0, sector=6491536, nr_sectors = 2 limit=128
Buffer I/O error on dev loop0, logical block 3245768, async page read
sysv_free_inode: unable to read inode block on device loop0