hpfs: Code page index out of array hpfs: code page support is disabled ================================================================== BUG: KASAN: use-after-free in strcmp+0x6b/0xc0 lib/string.c:283 Read of size 1 at addr ffff888068e3280d by task syz.1.3558/25492 CPU: 1 UID: 0 PID: 25492 Comm: syz.1.3558 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 strcmp+0x6b/0xc0 lib/string.c:283 hpfs_get_ea+0x134/0xee0 fs/hpfs/ea.c:139 hpfs_read_inode+0x1a6/0x1050 fs/hpfs/inode.c:63 hpfs_fill_super+0x123d/0x1fa0 fs/hpfs/super.c:651 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3762 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3838 do_mount fs/namespace.c:4161 [inline] __do_sys_mount fs/namespace.c:4350 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4327 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f568899d20a 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:00007f56897b6e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f56897b6ee0 RCX: 00007f568899d20a RDX: 000020000000a000 RSI: 0000200000009ec0 RDI: 00007f56897b6ea0 RBP: 000020000000a000 R08: 00007f56897b6ee0 R09: 0000000003a00041 R10: 0000000003a00041 R11: 0000000000000246 R12: 0000200000009ec0 R13: 00007f56897b6ea0 R14: 0000000000009e24 R15: 0000200000000000 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x200000212 pfn:0x68e32 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000200000212 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 25302, tgid 25296 (syz.6.3523), ts 1510688976099, free_ts 1512534852408 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2485 folio_alloc_mpol_noprof mm/mempolicy.c:2504 [inline] vma_alloc_folio_noprof+0xea/0x210 mm/mempolicy.c:2539 folio_prealloc mm/memory.c:-1 [inline] wp_page_copy mm/memory.c:3780 [inline] do_wp_page+0x1204/0x5a00 mm/memory.c:4241 handle_pte_fault mm/memory.c:6333 [inline] __handle_mm_fault mm/memory.c:6455 [inline] handle_mm_fault+0x1520/0x3310 mm/memory.c:6624 do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1385 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 page last free pid 25302 tgid 25296 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] free_unref_folios+0xed5/0x16d0 mm/page_alloc.c:3040 folios_put_refs+0x789/0x8d0 mm/swap.c:1002 free_pages_and_swap_cache+0x2e7/0x5b0 mm/swap_state.c:423 __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:398 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:405 zap_pte_range mm/memory.c:1968 [inline] zap_pmd_range mm/memory.c:2021 [inline] zap_pud_range mm/memory.c:2049 [inline] zap_p4d_range mm/memory.c:2070 [inline] unmap_page_range+0x3c1d/0x48f0 mm/memory.c:2091 unmap_single_vma mm/memory.c:2133 [inline] unmap_vmas+0x48f/0x6a0 mm/memory.c:2171 exit_mmap+0x280/0xa10 mm/mmap.c:1302 __mmput+0x118/0x430 kernel/fork.c:1174 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2320 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888068e32700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888068e32780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888068e32800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888068e32880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888068e32900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================