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loop0: detected capacity change from 0 to 128
VFS: Found a Xenix FS (block size = 1024) on device loop0
syz-executor170: 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
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BUG: KASAN: use-after-free in sysv_new_inode+0x107e/0x1210 fs/sysv/ialloc.c:153
Read of size 2 at addr ffff88806ea9e1ce by task syz-executor170/4248

CPU: 0 PID: 4248 Comm: syz-executor170 Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 sysv_new_inode+0x107e/0x1210 fs/sysv/ialloc.c:153
 sysv_symlink+0x9b/0x180 fs/sysv/namei.c:80
 vfs_symlink+0x247/0x3d0 fs/namei.c:4471
 do_symlinkat+0x21e/0x390 fs/namei.c:4500
 __do_sys_symlink fs/namei.c:4522 [inline]
 __se_sys_symlink fs/namei.c:4520 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4520
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f936e80f5a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffebd1da8b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f936e80f5a9
RDX: 00007f936e80e740 RSI: 00000000200059c0 RDI: 0000000020002840
RBP: 0000000000000000 R08: 0000000000009e7f R09: 00007ffebd1da8ec
R10: 00007ffebd1da780 R11: 0000000000000246 R12: 00007ffebd1da8ec
R13: 0000000000000002 R14: 431bde82d7b634db R15: 00007ffebd1da920
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001baa780 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x6ea9e
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001baa7c8 ffffea0001baa748 0000000000000000
raw: 0000000000000001 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 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 4236, tgid 4236 (sshd), ts 68771750349, free_ts 68809447447
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5590
 __folio_alloc+0xf/0x30 mm/page_alloc.c:5622
 vma_alloc_folio+0x486/0x990 mm/mempolicy.c:2243
 alloc_page_vma include/linux/gfp.h:284 [inline]
 do_anonymous_page mm/memory.c:4189 [inline]
 handle_pte_fault mm/memory.c:5027 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x2e8e/0x5340 mm/memory.c:5292
 do_user_addr_fault arch/x86/mm/fault.c:1340 [inline]
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x26f/0x620 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3510
 release_pages+0x2836/0x2b40 mm/swap.c:1055
 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
 tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261
 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361
 unmap_region+0x29f/0x2f0 mm/mmap.c:2331
 do_mas_align_munmap+0xef5/0x15a0 mm/mmap.c:2580
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2638
 __vm_munmap+0x268/0x370 mm/mmap.c:2924
 __do_sys_munmap mm/mmap.c:2949 [inline]
 __se_sys_munmap mm/mmap.c:2946 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2946
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88806ea9e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806ea9e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88806ea9e180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff88806ea9e200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806ea9e280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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