loop0: detected capacity change from 0 to 128
VFS: Found a Xenix FS (block size = 1024) on device loop0
syz.0.15: 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
==================================================================
BUG: KASAN: use-after-free in sysv_new_inode+0xfc3/0x1160 fs/sysv/ialloc.c:153
Read of size 2 at addr ffff88805ec1a1ce by task syz.0.15/6606

CPU: 0 UID: 0 PID: 6606 Comm: syz.0.15 Not tainted 6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x23d/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x165/0x540 mm/kasan/report.c:488
 kasan_report+0x13f/0x180 mm/kasan/report.c:601
 sysv_new_inode+0xfc3/0x1160 fs/sysv/ialloc.c:153
 sysv_symlink+0x9b/0x180 fs/sysv/namei.c:80
 vfs_symlink+0x133/0x2e0 fs/namei.c:4615
 do_symlinkat+0x21e/0x3a0 fs/namei.c:4641
 __do_sys_symlink fs/namei.c:4662 [inline]
 __se_sys_symlink fs/namei.c:4660 [inline]
 __x64_sys_symlink+0x76/0x90 fs/namei.c:4660
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x7e/0x180 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7efd6b97e719
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efd6c840038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007efd6bb35f80 RCX: 00007efd6b97e719
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000020000080
RBP: 00007efd6b9f132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007efd6bb35f80 R15: 00007fff4ec012c8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x2c9 pfn:0x5ec1a
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 00000000000002c9 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 6419, tgid 6419 (syz-executor), ts 123555668436, free_ts 123932189539
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1df/0x220 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3a30/0x3c90 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x25d/0x690 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e4/0x670 mm/mempolicy.c:2265
 folio_alloc_mpol_noprof mm/mempolicy.c:2283 [inline]
 vma_alloc_folio_noprof+0x12a/0x230 mm/mempolicy.c:2314
 folio_prealloc+0x31/0x170
 do_cow_fault mm/memory.c:5310 [inline]
 do_fault mm/memory.c:5422 [inline]
 do_pte_missing mm/memory.c:3965 [inline]
 handle_pte_fault+0xd50/0x6710 mm/memory.c:5755
 __handle_mm_fault mm/memory.c:5898 [inline]
 handle_mm_fault+0x1022/0x1950 mm/memory.c:6066
 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x3e8/0x7e0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:623
page last free pid 6427 tgid 6427 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_folios+0xee0/0x1880 mm/page_alloc.c:2686
 folios_put_refs+0x764/0x860 mm/swap.c:1007
 free_pages_and_swap_cache+0x2e6/0x690 mm/swap_state.c:332
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x39f/0x670 mm/mmu_gather.c:373
 tlb_finish_mmu+0xd0/0x1f0 mm/mmu_gather.c:465
 exit_mmap+0x492/0xc00 mm/mmap.c:1887
 __mmput+0x115/0x390 kernel/fork.c:1347
 exit_mm+0x21c/0x300 kernel/exit.c:571
 do_exit+0x9ae/0x28d0 kernel/exit.c:926
 do_group_exit+0x203/0x2b0 kernel/exit.c:1088
 get_signal+0x169f/0x1730 kernel/signal.c:2917
 arch_do_signal_or_restart+0x92/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc4/0x350 kernel/entry/common.c:218
 do_syscall_64+0x8a/0x180 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Memory state around the buggy address:
 ffff88805ec1a080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805ec1a100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88805ec1a180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff88805ec1a200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805ec1a280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================