hpfs: filesystem error: invalid number of hotfixes: 2066844986, used: 2066844985; going on - but anything won't be destroyed because it's read-only
hpfs: filesystem error: improperly stopped
hpfs: You really don't want any checks? You are crazy...
hpfs: Code page directory magic doesn't match (magic = 7b3184b5)
hpfs: code page support is disabled
==================================================================
BUG: KASAN: use-after-free in strcmp+0x6f/0xc0 lib/string.c:283
Read of size 1 at addr ffff88806b5bb8a6 by task syz.3.187/7079

CPU: 1 UID: 0 PID: 7079 Comm: syz.3.187 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 strcmp+0x6f/0xc0 lib/string.c:283
 hpfs_get_ea+0x114/0xdb0 fs/hpfs/ea.c:139
 hpfs_read_inode+0x19d/0x1010 fs/hpfs/inode.c:63
 hpfs_fill_super+0x129d/0x2040 fs/hpfs/super.c:651
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f22d8b90eea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f22d9a8be68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f22d9a8bef0 RCX: 00007f22d8b90eea
RDX: 000020000000a000 RSI: 0000200000009ec0 RDI: 00007f22d9a8beb0
RBP: 000020000000a000 R08: 00007f22d9a8bef0 R09: 0000000003a00041
R10: 0000000003a00041 R11: 0000000000000246 R12: 0000200000009ec0
R13: 00007f22d9a8beb0 R14: 0000000000009e24 R15: 0000200000000100
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x8e5 pfn:0x6b5bb
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001ad6e88 ffffea0001ad6f08 0000000000000000
raw: 00000000000008e5 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 6956, tgid 6955 (syz.2.168), ts 160252766361, free_ts 161460077278
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857
 prep_new_page mm/page_alloc.c:1865 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505
 shmem_alloc_folio mm/shmem.c:1902 [inline]
 shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1944
 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2568
 shmem_get_folio mm/shmem.c:2674 [inline]
 shmem_write_begin+0x16c/0x330 mm/shmem.c:3327
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3502
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 6956 tgid 6955 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1406 [inline]
 free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000
 folios_put_refs+0x584/0x670 mm/swap.c:1002
 folio_batch_release include/linux/pagevec.h:101 [inline]
 shmem_undo_range+0x49e/0x1490 mm/shmem.c:1137
 shmem_truncate_range mm/shmem.c:1249 [inline]
 shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
 evict+0x5f4/0xae0 fs/inode.c:837
 __dentry_kill+0x209/0x660 fs/dcache.c:670
 finish_dput+0xc9/0x480 fs/dcache.c:879
 __fput+0x68e/0xa70 fs/file_table.c:476
 fput_close_sync+0x113/0x220 fs/file_table.c:573
 __do_sys_close fs/open.c:1534 [inline]
 __se_sys_close fs/open.c:1519 [inline]
 __x64_sys_close+0x7f/0x110 fs/open.c:1519
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88806b5bb780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806b5bb800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88806b5bb880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                               ^
 ffff88806b5bb900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806b5bb980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================