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loop0: detected capacity change from 0 to 128
VFS: Found a Xenix FS (block size = 1024) on device loop0
syz-executor242: 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+0x107e/0x1210 fs/sysv/ialloc.c:153
Read of size 2 at addr ffff8880673371ce by task syz-executor242/4256

CPU: 0 PID: 4256 Comm: syz-executor242 Not tainted 6.1.114-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: 0033:0x7f11d1247209
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 1f 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f11d09f6168 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007f11d12d26c8 RCX: 00007f11d1247209
RDX: 00007f11d1247209 RSI: 0000000020000000 RDI: 0000000020000080
RBP: 00007f11d12d26c0 R08: 00007f11d09f66c0 R09: 0000000000000000
R10: 0000000000009e89 R11: 0000000000000246 R12: 00007f11d12d26cc
R13: 0000000000000010 R14: 00007ffd0640ff40 R15: 00007ffd06410028
 </TASK>

The buggy address belongs to the physical page:
page:ffffea00019ccdc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x67337
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea00019cce08 ffffea00019ccd88 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 0x8(__GFP_MOVABLE), pid 1, tgid 1 (swapper/0), ts 19369862993, free_ts 20595765712
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 split_map_pages+0x246/0x510 mm/compaction.c:97
 isolate_freepages_range+0x47c/0x4e0 mm/compaction.c:735
 alloc_contig_range+0x62a/0x990 mm/page_alloc.c:9393
 __alloc_contig_pages mm/page_alloc.c:9416 [inline]
 alloc_contig_pages+0x3f0/0x4e0 mm/page_alloc.c:9496
 debug_vm_pgtable_alloc_huge_page+0xb9/0x108 mm/debug_vm_pgtable.c:1098
 init_args+0xc92/0x1022 mm/debug_vm_pgtable.c:1221
 debug_vm_pgtable+0xaa/0x46b mm/debug_vm_pgtable.c:1259
 do_one_initcall+0x265/0x8f0 init/main.c:1298
 do_initcall_level+0x157/0x207 init/main.c:1371
 do_initcalls+0x49/0x86 init/main.c:1387
 kernel_init_freeable+0x45c/0x60f init/main.c:1626
 kernel_init+0x19/0x290 init/main.c:1514
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
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+0x33/0x3e0 mm/page_alloc.c:3464
 free_contig_range+0x9a/0x150 mm/page_alloc.c:9518
 destroy_args+0xfe/0x997 mm/debug_vm_pgtable.c:1031
 debug_vm_pgtable+0x416/0x46b mm/debug_vm_pgtable.c:1354
 do_one_initcall+0x265/0x8f0 init/main.c:1298
 do_initcall_level+0x157/0x207 init/main.c:1371
 do_initcalls+0x49/0x86 init/main.c:1387
 kernel_init_freeable+0x45c/0x60f init/main.c:1626
 kernel_init+0x19/0x290 init/main.c:1514
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888067337080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888067337100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888067337180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff888067337200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888067337280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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