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KASAN: use-after-free Read in ntfs_test_inode (3)

Status: upstream: reported on 2026/03/24 00:25
Reported-by: syzbot+13c551b604b60d334be3@syzkaller.appspotmail.com
First crash: 4d08h, last: 4d08h
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in ntfs_test_inode (2) 19 20 143d 579d 0/3 auto-obsoleted due to no activity on 2026/02/13 06:39
linux-6.1 KASAN: use-after-free Read in ntfs_test_inode (2) 19 13 31d 442d 0/3 upstream: reported on 2025/01/09 09:49
linux-4.19 KASAN: use-after-free Read in ntfs_test_inode 19 1 1215d 1215d 0/1 auto-obsoleted due to no activity on 2023/03/28 18:25
upstream KASAN: use-after-free Read in ntfs_test_inode ntfs3 19 C done 402 841d 1775d 25/29 fixed on 2023/12/21 01:43
linux-6.1 KASAN: use-after-free Read in ntfs_test_inode 19 2 732d 735d 0/3 auto-obsoleted due to no activity on 2024/07/03 10:22
linux-5.15 KASAN: use-after-free Read in ntfs_test_inode 19 6 899d 1098d 0/3 auto-obsoleted due to no activity on 2024/01/19 06:00
upstream KASAN: slab-use-after-free Read in ntfs_test_inode fs 19 5 808d 808d 0/29 auto-obsoleted due to no activity on 2024/04/18 20:01
linux-6.6 KASAN: slab-use-after-free Read in ntfs_test_inode 19 4 16d 66d 0/2 upstream: reported on 2026/01/20 09:45
linux-4.14 KASAN: slab-out-of-bounds Read in ntfs_test_inode 17 1 1500d 1500d 0/1 auto-closed as invalid on 2022/06/16 22:11

Sample crash report:
loop1: detected capacity change from 0 to 4096
ntfs: volume version 3.1.
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: use-after-free in NInoAttr fs/ntfs/inode.h:200 [inline]
BUG: KASAN: use-after-free in ntfs_test_inode+0x79/0x2d0 fs/ntfs/inode.c:55
Read of size 8 at addr ffff88805ae50560 by task syz.1.2946/10341

CPU: 0 PID: 10341 Comm: syz.1.2946 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 NInoAttr fs/ntfs/inode.h:200 [inline]
 ntfs_test_inode+0x79/0x2d0 fs/ntfs/inode.c:55
 find_inode+0x19a/0x3f0 fs/inode.c:898
 ilookup5_nowait fs/inode.c:1450 [inline]
 ilookup5+0x9f/0x1f0 fs/inode.c:1479
 iget5_locked+0x30/0x250 fs/inode.c:1260
 ntfs_iget+0xb9/0x1a0 fs/ntfs/inode.c:168
 load_and_check_logfile+0x3f/0xd0 fs/ntfs/super.c:1208
 load_system_files+0x3a76/0x55a0 fs/ntfs/super.c:1941
 ntfs_fill_super+0x19e0/0x2c90 fs/ntfs/super.c:2894
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc0f22c1a0a
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:00007fc0f0519e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc0f0519ee0 RCX: 00007fc0f22c1a0a
RDX: 0000200000000000 RSI: 0000200000000340 RDI: 00007fc0f0519ea0
RBP: 0000200000000000 R08: 00007fc0f0519ee0 R09: 0000000000814802
R10: 0000000000814802 R11: 0000000000000246 R12: 0000200000000340
R13: 00007fc0f0519ea0 R14: 000000000001ee6d R15: 0000200000000100
 </TASK>

Allocated by task 7984:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
 reiserfs_alloc_inode+0x19/0xb0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0x9e/0x250 fs/inode.c:1263
 reiserfs_fill_super+0x122d/0x2440 fs/reiserfs/super.c:2057
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Last potentially related work creation:
 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3011 [inline]
 call_rcu+0x189/0x950 kernel/rcu/tree.c:3091
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:662
 dispose_list fs/inode.c:680 [inline]
 evict_inodes+0x60c/0x6a0 fs/inode.c:734
 generic_shutdown_super+0x93/0x300 fs/super.c:454
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to last potentially related work creation:
 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3011 [inline]
 call_rcu+0x189/0x950 kernel/rcu/tree.c:3091
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:662
 reiserfs_fill_super+0x14c4/0x2440 fs/reiserfs/super.c:2082
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88805ae50000
 which belongs to the cache reiser_inode_cache of size 1568
The buggy address is located 1376 bytes inside of
 1568-byte region [ffff88805ae50000, ffff88805ae50620)
The buggy address belongs to the page:
page:ffffea00016b9400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805ae51a80 pfn:0x5ae50
head:ffffea00016b9400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888025207601
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801e0ba280
raw: ffff88805ae51a80 000000008013000f 00000001ffffffff ffff888025207601
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 6886, ts 149593296710, free_ts 11463655974
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x195/0x290 mm/slub.c:3238
 reiserfs_alloc_inode+0x19/0xb0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0x9e/0x250 fs/inode.c:1263
 reiserfs_fill_super+0x122d/0x2440 fs/reiserfs/super.c:2057
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428
 destroy_args+0xf0/0xa00 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336
 do_one_initcall+0x272/0x730 init/main.c:1316
 do_initcall_level+0x137/0x1f0 init/main.c:1389
 do_initcalls+0x4b/0x90 init/main.c:1405
 kernel_init_freeable+0x3e9/0x570 init/main.c:1629
 kernel_init+0x19/0x1b0 init/main.c:1520
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88805ae50400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805ae50480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805ae50500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff88805ae50580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805ae50600: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/24 00:24 linux-5.15.y 91d48252ad4b baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_test_inode
* Struck through repros no longer work on HEAD.