hpfs: Proceeding, but your filesystem could be corrupted if you delete files or directories
hpfs: You really don't want any checks? You are crazy...
hpfs: hpfs_map_sector(): read error
hpfs: code page support is disabled
==================================================================
BUG: KASAN: use-after-free in strcmp+0x6b/0xc0 lib/string.c:265
Read of size 1 at addr ffff88804613c8a6 by task syz.6.524/8201

CPU: 1 UID: 0 PID: 8201 Comm: syz.6.524 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 strcmp+0x6b/0xc0 lib/string.c:265
 hpfs_get_ea+0x137/0xeb0 fs/hpfs/ea.c:139
 hpfs_read_inode+0x1a9/0x1060 fs/hpfs/inode.c:63
 hpfs_fill_super+0x1275/0x1fa0 fs/hpfs/super.c:652
 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1887
 vfs_get_tree+0x92/0x2a0 fs/super.c:1947
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3772 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3848
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4374
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f473299f34a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f473392ee58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f473392eee0 RCX: 00007f473299f34a
RDX: 0000200000000000 RSI: 0000200000000040 RDI: 00007f473392eea0
RBP: 0000200000000000 R08: 00007f473392eee0 R09: 0000000003200041
R10: 0000000003200041 R11: 0000000000000246 R12: 0000200000000040
R13: 00007f473392eea0 R14: 0000000000009e30 R15: 0000200000000080
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x7f4728ebf pfn:0x4613c
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 00000007f4728ebf 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_ZERO|__GFP_COMP), pid 8045, tgid 8044 (syz.6.482), ts 235346805367
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436
 alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2486
 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2505
 vma_alloc_folio_noprof+0xe1/0x1e0 mm/mempolicy.c:2540
 folio_prealloc mm/memory.c:-1 [inline]
 alloc_anon_folio mm/memory.c:5387 [inline]
 do_anonymous_page mm/memory.c:5482 [inline]
 do_pte_missing+0x173a/0x34b0 mm/memory.c:4698
 handle_pte_fault mm/memory.c:6558 [inline]
 __handle_mm_fault mm/memory.c:6707 [inline]
 handle_mm_fault+0x1a53/0x3750 mm/memory.c:6876
 do_user_addr_fault+0xa4f/0x1340 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
page last free pid 8045 tgid 8044 ts 236514773544 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 free_unref_folios+0xdc2/0x14e0 mm/page_alloc.c:3022
 folios_put_refs+0x9e9/0xb30 mm/folio.c:1034
 free_pages_and_swap_cache+0x2ba/0x490 mm/swap_state.c:592
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:151 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:417 [inline]
 tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:424
 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549
 unmap_region+0x2a5/0x330 mm/vma.c:535
 vms_clear_ptes mm/vma.c:1383 [inline]
 vms_complete_munmap_vmas+0x427/0xbe0 mm/vma.c:1425
 do_vmi_align_munmap+0x3b7/0x4b0 mm/vma.c:1684
 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1732
 __vm_munmap+0x241/0x3e0 mm/vma.c:3390
 __do_sys_munmap mm/mmap.c:1094 [inline]
 __se_sys_munmap mm/mmap.c:1091 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1091
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804613c780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804613c800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88804613c880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                               ^
 ffff88804613c900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804613c980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================