syzbot


KASAN: use-after-free Read in ntfs_test_inode (2)

Status: upstream: reported on 2025/01/09 09:49
Reported-by: syzbot+07c590b4c6dd83fd7888@syzkaller.appspotmail.com
First crash: 404d, last: 4d17h
Similar bugs (8)
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 104d 540d 0/3 auto-obsoleted due to no activity on 2026/02/13 06:39
linux-4.19 KASAN: use-after-free Read in ntfs_test_inode 19 1 1177d 1177d 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 803d 1737d 25/29 fixed on 2023/12/21 01:43
linux-6.1 KASAN: use-after-free Read in ntfs_test_inode 19 2 694d 696d 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 860d 1060d 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 770d 770d 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 3 7d11h 28d 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 1462d 1462d 0/1 auto-closed as invalid on 2022/06/16 22:11

Sample crash report:
ntfs: (device loop2): load_and_init_upcase(): Failed to load $UpCase from the volume. Using default.
ntfs: volume version 3.1.
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:72 [inline]
BUG: KASAN: use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [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 ffff888071c8d4e0 by task syz.2.7600/21668

CPU: 0 PID: 21668 Comm: syz.2.7600 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 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:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [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:960
 ilookup5_nowait fs/inode.c:1515 [inline]
 ilookup5+0xa7/0x1e0 fs/inode.c:1544
 iget5_locked+0x30/0x260 fs/inode.c:1325
 ntfs_iget+0xb9/0x1a0 fs/ntfs/inode.c:168
 load_and_check_logfile+0x3f/0xd0 fs/ntfs/super.c:1208
 load_system_files+0x2f17/0x4540 fs/ntfs/super.c:1941
 ntfs_fill_super+0x182a/0x2a60 fs/ntfs/super.c:2892
 mount_bdev+0x287/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5d72f9c14a
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:00007f5d711f5e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f5d711f5ee0 RCX: 00007f5d72f9c14a
RDX: 0000200000000100 RSI: 0000200000000000 RDI: 00007f5d711f5ea0
RBP: 0000200000000100 R08: 00007f5d711f5ee0 R09: 0000000001800010
R10: 0000000001800010 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f5d711f5ea0 R14: 000000000001ee86 R15: 000020000001f340
 </TASK>

Allocated by task 19245:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 reiserfs_alloc_inode+0x26/0xc0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0x9e/0x260 fs/inode.c:1328
 reiserfs_fill_super+0x11d3/0x23b0 fs/reiserfs/super.c:2053
 mount_bdev+0x287/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:720
 dispose_list fs/inode.c:738 [inline]
 evict_inodes+0x60c/0x6a0 fs/inode.c:792
 generic_shutdown_super+0x93/0x340 fs/super.c:480
 kill_block_super+0x7c/0xe0 fs/super.c:1470
 deactivate_locked_super+0x93/0xf0 fs/super.c:332
 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Second to last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:720
 reiserfs_fill_super+0x1475/0x23b0 fs/reiserfs/super.c:2078
 mount_bdev+0x287/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888071c8cf80
 which belongs to the cache reiser_inode_cache of size 1568
The buggy address is located 1376 bytes inside of
 1568-byte region [ffff888071c8cf80, ffff888071c8d5a0)

The buggy address belongs to the physical page:
page:ffffea0001c72200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888071c8e360 pfn:0x71c88
head:ffffea0001c72200 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88802857fb01
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888145abba00
raw: ffff888071c8e360 0000000080130004 00000001ffffffff ffff88802857fb01
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 4654, tgid 4653 (syz.4.118), ts 90087341174, free_ts 89269131069
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4328
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5614
 alloc_slab_page+0x5d/0x160 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1997
 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3390
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 reiserfs_alloc_inode+0x26/0xc0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0x9e/0x260 fs/inode.c:1328
 reiserfs_fill_super+0x11d3/0x23b0 fs/reiserfs/super.c:2053
 mount_bdev+0x287/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
 getname_flags+0xb7/0x500 fs/namei.c:139
 user_path_at_empty+0x28/0x60 fs/namei.c:2912
 do_readlinkat+0xd9/0x490 fs/stat.c:468
 __do_sys_readlink fs/stat.c:501 [inline]
 __se_sys_readlink fs/stat.c:498 [inline]
 __x64_sys_readlink+0x7b/0x90 fs/stat.c:498
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff888071c8d380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888071c8d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888071c8d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff888071c8d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888071c8d580: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/30 11:41 linux-6.1.y cd9b81672742 ae7dc18c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in ntfs_test_inode
2025/08/29 22:42 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in ntfs_test_inode
2025/05/24 03:45 linux-6.1.y da3c5173c55f ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in ntfs_test_inode
2025/01/09 09:48 linux-6.1.y 7dc732d24ff7 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in ntfs_test_inode
2026/02/13 04:46 linux-6.1.y 8ce36b2849ef 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in ntfs_test_inode
2025/05/15 09:32 linux-6.1.y 02b72ccb5f9d d6b2ee52 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in ntfs_test_inode
2025/03/27 12:46 linux-6.1.y 344a09659766 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in ntfs_test_inode
2025/01/17 11:47 linux-6.1.y c63962be84ef 953d1c45 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in ntfs_test_inode
2026/02/07 17:48 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Read in ntfs_test_inode
2025/11/19 18:05 linux-6.1.y f6e38ae624cf 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in ntfs_test_inode
2025/03/05 22:07 linux-6.1.y 3a8358583626 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in ntfs_test_inode
* Struck through repros no longer work on HEAD.