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: slab-use-after-free in strcmp+0x6f/0xc0 lib/string.c:283 Read of size 1 at addr ffff888011a968a6 by task syz.0.16/5983 CPU: 0 UID: 0 PID: 5983 Comm: syz.0.16 Not tainted 6.16.0-rc7-syzkaller-00142-gb711733e89a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: 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+0x12bd/0x2070 fs/hpfs/super.c:654 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1681 vfs_get_tree+0x92/0x2b0 fs/super.c:1804 do_new_mount+0x24a/0xa40 fs/namespace.c:3902 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4427 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7ffe19014a 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:00007ffe954e1418 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ffe954e14a0 RCX: 00007f7ffe19014a RDX: 0000200000009e80 RSI: 0000200000009ec0 RDI: 00007ffe954e1460 RBP: 0000200000009e80 R08: 00007ffe954e14a0 R09: 0000000000000041 R10: 0000000000000041 R11: 0000000000000246 R12: 0000200000009ec0 R13: 00007ffe954e1460 R14: 0000000000009e05 R15: 0000200000009f00 Allocated by task 5771: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 ptlock_alloc+0x20/0x70 mm/memory.c:7174 ptlock_init include/linux/mm.h:2939 [inline] pagetable_pte_ctor include/linux/mm.h:2988 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:78 [inline] pte_alloc_one+0x7d/0x170 arch/x86/mm/pgtable.c:18 __pte_alloc+0x25/0x1a0 mm/memory.c:441 copy_pte_range mm/memory.c:1112 [inline] copy_pmd_range+0x68e6/0x7000 mm/memory.c:1267 copy_pud_range mm/memory.c:1304 [inline] copy_p4d_range mm/memory.c:1328 [inline] copy_page_range+0xc46/0x1270 mm/memory.c:1416 dup_mmap+0xf57/0x1ac0 mm/mmap.c:1838 dup_mm kernel/fork.c:1477 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1529 copy_process+0x16d3/0x3b80 kernel/fork.c:2169 kernel_clone+0x224/0x7f0 kernel/fork.c:2599 __do_sys_clone kernel/fork.c:2742 [inline] __se_sys_clone kernel/fork.c:2726 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4745 pagetable_dtor include/linux/mm.h:2974 [inline] pagetable_dtor_free include/linux/mm.h:2981 [inline] __tlb_remove_table+0x81/0x3b0 include/asm-generic/tlb.h:220 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x283/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff888011a968a0 which belongs to the cache page->ptl of size 64 The buggy address is located 6 bytes inside of freed 64-byte region [ffff888011a968a0, ffff888011a968e0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888011a961e0 pfn:0x11a96 anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801a44b780 0000000000000000 0000000000000001 raw: ffff888011a961e0 00000000002a0023 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5771, tgid 5771 (dhcpcd-run-hook), ts 78116845101, free_ts 78034110984 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21d5/0x22b0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4204 ptlock_alloc mm/memory.c:7174 [inline] ptlock_init include/linux/mm.h:2939 [inline] pmd_ptlock_init include/linux/mm.h:3067 [inline] pagetable_pmd_ctor include/linux/mm.h:3095 [inline] pmd_alloc_one_noprof include/asm-generic/pgalloc.h:145 [inline] __pmd_alloc+0xc6/0x3b0 mm/memory.c:6467 pmd_alloc include/linux/mm.h:2830 [inline] copy_pmd_range+0x6bfc/0x7000 mm/memory.c:1247 copy_pud_range mm/memory.c:1304 [inline] copy_p4d_range mm/memory.c:1328 [inline] copy_page_range+0xc46/0x1270 mm/memory.c:1416 dup_mmap+0xf57/0x1ac0 mm/mmap.c:1838 dup_mm kernel/fork.c:1477 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1529 copy_process+0x16d3/0x3b80 kernel/fork.c:2169 kernel_clone+0x224/0x7f0 kernel/fork.c:2599 __do_sys_clone kernel/fork.c:2742 [inline] __se_sys_clone kernel/fork.c:2726 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 page last free pid 15 tgid 15 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706 pagetable_free include/linux/mm.h:2884 [inline] pagetable_dtor_free include/linux/mm.h:2982 [inline] __tlb_remove_table+0x2d2/0x3b0 include/asm-generic/tlb.h:220 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x283/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888011a96780: fa fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ffff888011a96800: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fb >ffff888011a96880: fc fc fc fc fa fb fb fb fb fb fb fb fc fc fc fc ^ ffff888011a96900: fa fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ffff888011a96980: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================