================================================================== BUG: KASAN: slab-use-after-free in ntfs_show_options+0x69f/0x860 fs/ntfs3/super.c:774 Read of size 2 at addr ffff88807cd7b89c by task syz-executor420/6012 CPU: 1 UID: 0 PID: 6012 Comm: syz-executor420 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026 Call Trace: 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 ntfs_show_options+0x69f/0x860 fs/ntfs3/super.c:774 show_vfsmnt+0x646/0x790 fs/proc_namespace.c:129 seq_read_iter+0x8d5/0xca0 fs/seq_file.c:273 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x595/0xa80 fs/read_write.c:574 ksys_read+0x150/0x270 fs/read_write.c:716 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: 0033:0x7f90dd8ad61e Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08 RSP: 002b:00007f90dd04c198 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f90dd04d6c0 RCX: 00007f90dd8ad61e RDX: 0000000000001000 RSI: 00007f90dd04c200 RDI: 0000000000000005 RBP: 00007f90dd8f203e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f90dd04c200 R13: 0000000000000000 R14: 00007ffe29b2b870 R15: 00007ffe29b2b958 Allocated by task 6019: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x321/0x600 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] ntfs_init_fs_context+0x55/0x570 fs/ntfs3/super.c:1887 alloc_fs_context+0x9a3/0xd00 fs/fs_context.c:295 do_remount fs/namespace.c:3395 [inline] path_mount+0xc5e/0x1050 fs/namespace.c:4160 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 Freed by task 6023: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 put_fs_context+0x123/0xb00 fs/fs_context.c:498 do_remount fs/namespace.c:3422 [inline] path_mount+0xefc/0x1050 fs/namespace.c:4160 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 The buggy address belongs to the object at ffff88807cd7b880 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 28 bytes inside of freed 32-byte region [ffff88807cd7b880, ffff88807cd7b8a0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7cd7b flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b041780 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000400040 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5350, tgid 5350 (start-stop-daem), ts 50764153307 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_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __kmalloc_cache_noprof+0x39b/0x600 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] slab_free_hook mm/slub.c:2700 [inline] slab_free mm/slub.c:6499 [inline] kmem_cache_free+0x156/0x650 mm/slub.c:6626 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x73a/0x2360 kernel/exit.c:1008 do_group_exit+0x22d/0x2f0 kernel/exit.c:1151 __do_sys_exit_group kernel/exit.c:1162 [inline] __se_sys_exit_group kernel/exit.c:1160 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1160 x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232 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 page last free pid 5350 tgid 5350 ts 50761077561 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962 tlb_batch_list_free mm/mmu_gather.c:161 [inline] tlb_finish_mmu+0x13e/0x220 mm/mmu_gather.c:552 exit_mmap+0x4b2/0x9f0 mm/mmap.c:1328 __mmput+0x118/0x420 kernel/fork.c:1193 exit_mm+0x221/0x2d0 kernel/exit.c:614 do_exit+0x6cd/0x2360 kernel/exit.c:996 do_group_exit+0x22d/0x2f0 kernel/exit.c:1151 __do_sys_exit_group kernel/exit.c:1162 [inline] __se_sys_exit_group kernel/exit.c:1160 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1160 x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232 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: ffff88807cd7b780: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc ffff88807cd7b800: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc >ffff88807cd7b880: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ^ ffff88807cd7b900: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ffff88807cd7b980: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc ==================================================================