KMSAN: uninit-value in ntfs_read_hdr (4)

Status: auto-obsoleted due to no activity on 2026/05/10 14:12
Subsystems: ntfs3
[Documentation on labels]
Reported-by: syzbot+2472d48b2d3b2a23a570@syzkaller.appspotmail.com
First crash: 202d, last: 187d
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ID Workflow Result Correct Bug Created Started Finished Revision
1f13009a repro ❓ KMSAN: uninit-value in ntfs_read_hdr (4) 2026/03/08 05:17 2026/03/08 05:17 2026/03/08 05:26 31e9c887
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Title Replies (including bot) Last reply
[syzbot] [ntfs3?] KMSAN: uninit-value in ntfs_read_hdr (4) 0 (1) 2026/01/19 21:56
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in ntfs_read_hdr (3) ntfs3 7 syz, C 6 215d 322d 29/29 fixed on 2026/01/07 12:29
upstream KMSAN: uninit-value in ntfs_read_hdr (2) ntfs3 7 1 464d 460d 0/29 auto-obsoleted due to no activity on 2025/08/06 10:39
upstream KMSAN: uninit-value in ntfs_read_hdr ntfs3 7 15 578d 634d 0/29 auto-obsoleted due to no activity on 2025/03/15 12:38
upstream KASAN: slab-use-after-free Read in ntfs_read_hdr actionable prio:high ntfs3 19 2 77d 65d 0/29 upstream: reported on 2026/06/01 20:12

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in ntfs_dir_emit fs/ntfs3/dir.c:335 [inline]
BUG: KMSAN: uninit-value in ntfs_read_hdr+0xfd2/0x1440 fs/ntfs3/dir.c:384
 ntfs_dir_emit fs/ntfs3/dir.c:335 [inline]
 ntfs_read_hdr+0xfd2/0x1440 fs/ntfs3/dir.c:384
 ntfs_readdir+0xf21/0x1a30 fs/ntfs3/dir.c:495
 iterate_dir+0x459/0x630 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:412 [inline]
 __se_sys_getdents64+0x17e/0x550 fs/readdir.c:397
 __x64_sys_getdents64+0x97/0xe0 fs/readdir.c:397
 x64_sys_call+0x3cef/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:218
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

<Zero or more stacks not recorded to save memory>

Uninit was stored to memory at:
 ntfs_write_bh+0x6ae/0xe90 fs/ntfs3/fsntfs.c:1437
 indx_write fs/ntfs3/index.c:1027 [inline]
 indx_insert_into_buffer+0x287/0x2010 fs/ntfs3/index.c:1819
 indx_insert_entry+0xcde/0x1050 fs/ntfs3/index.c:1997
 ntfs_create_inode+0x3ee3/0x57b0 fs/ntfs3/inode.c:1656
 ntfs_create+0x56/0x70 fs/ntfs3/namei.c:110
 lookup_open fs/namei.c:4449 [inline]
 open_last_lookups fs/namei.c:4549 [inline]
 path_openat+0x37dd/0x7160 fs/namei.c:4793
 do_filp_open+0x27f/0x660 fs/namei.c:4823
 do_sys_openat2+0x1c6/0x430 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_creat fs/open.c:1514 [inline]
 __se_sys_creat fs/open.c:1508 [inline]
 __x64_sys_creat+0xe1/0x150 fs/open.c:1508
 x64_sys_call+0x3cdb/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:86
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 hdr_insert_de+0x471/0x560 fs/ntfs3/index.c:835
 indx_insert_into_buffer+0x1b6/0x2010 fs/ntfs3/index.c:1815
 indx_insert_entry+0xcde/0x1050 fs/ntfs3/index.c:1997
 ntfs_create_inode+0x3ee3/0x57b0 fs/ntfs3/inode.c:1656
 ntfs_create+0x56/0x70 fs/ntfs3/namei.c:110
 lookup_open fs/namei.c:4449 [inline]
 open_last_lookups fs/namei.c:4549 [inline]
 path_openat+0x37dd/0x7160 fs/namei.c:4793
 do_filp_open+0x27f/0x660 fs/namei.c:4823
 do_sys_openat2+0x1c6/0x430 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_creat fs/open.c:1514 [inline]
 __se_sys_creat fs/open.c:1508 [inline]
 __x64_sys_creat+0xe1/0x150 fs/open.c:1508
 x64_sys_call+0x3cdb/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:86
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 ntfs_read_run_nb+0x7cf/0x1810 fs/ntfs3/fsntfs.c:1232
 ntfs_read_bh+0x6a/0xc10 fs/ntfs3/fsntfs.c:1293
 indx_read+0x447/0x1820 fs/ntfs3/index.c:1067
 indx_find+0xa80/0x1500 fs/ntfs3/index.c:1179
 indx_insert_entry+0xd74/0x1050 fs/ntfs3/index.c:1974
 ntfs_create_inode+0x3ee3/0x57b0 fs/ntfs3/inode.c:1656
 ntfs_create+0x56/0x70 fs/ntfs3/namei.c:110
 lookup_open fs/namei.c:4449 [inline]
 open_last_lookups fs/namei.c:4549 [inline]
 path_openat+0x37dd/0x7160 fs/namei.c:4793
 do_filp_open+0x27f/0x660 fs/namei.c:4823
 do_sys_openat2+0x1c6/0x430 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_creat fs/open.c:1514 [inline]
 __se_sys_creat fs/open.c:1508 [inline]
 __x64_sys_creat+0xe1/0x150 fs/open.c:1508
 x64_sys_call+0x3cdb/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:86
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 ntfs_write_bh+0x6ae/0xe90 fs/ntfs3/fsntfs.c:1437
 indx_write fs/ntfs3/index.c:1027 [inline]
 indx_delete_entry+0x27c5/0x88c0 fs/ntfs3/index.c:2347
 ni_remove_name+0x33d/0xdb0 fs/ntfs3/frecord.c:2805
 ni_rename+0x170/0x220 fs/ntfs3/frecord.c:2965
 ntfs_rename+0xdd2/0x1290 fs/ntfs3/namei.c:332
 vfs_rename+0x249d/0x29a0 fs/namei.c:5938
 do_renameat2+0xb7f/0x15a0 fs/namei.c:6056
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0xd7/0x140 fs/namei.c:6097
 x64_sys_call+0x2c5/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 ntfs_read_run_nb+0x7cf/0x1810 fs/ntfs3/fsntfs.c:1232
 ntfs_read_bh+0x6a/0xc10 fs/ntfs3/fsntfs.c:1293
 indx_read+0x447/0x1820 fs/ntfs3/index.c:1067
 indx_find+0xa80/0x1500 fs/ntfs3/index.c:1179
 indx_delete_entry+0x117f/0x88c0 fs/ntfs3/index.c:2311
 ni_remove_name+0x33d/0xdb0 fs/ntfs3/frecord.c:2805
 ni_rename+0x170/0x220 fs/ntfs3/frecord.c:2965
 ntfs_rename+0xdd2/0x1290 fs/ntfs3/namei.c:332
 vfs_rename+0x249d/0x29a0 fs/namei.c:5938
 do_renameat2+0xb7f/0x15a0 fs/namei.c:6056
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0xd7/0x140 fs/namei.c:6097
 x64_sys_call+0x2c5/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 ntfs_write_bh+0x6ae/0xe90 fs/ntfs3/fsntfs.c:1437
 indx_write fs/ntfs3/index.c:1027 [inline]
 indx_insert_into_buffer+0x287/0x2010 fs/ntfs3/index.c:1819
 indx_insert_entry+0xcde/0x1050 fs/ntfs3/index.c:1997
 ni_add_name+0xef7/0x11e0 fs/ntfs3/frecord.c:2931
 ni_rename+0x97/0x220 fs/ntfs3/frecord.c:2962
 ntfs_rename+0xdd2/0x1290 fs/ntfs3/namei.c:332
 vfs_rename+0x249d/0x29a0 fs/namei.c:5938
 do_renameat2+0xb7f/0x15a0 fs/namei.c:6056
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0xd7/0x140 fs/namei.c:6097
 x64_sys_call+0x2c5/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 hdr_insert_de+0x4cc/0x560 fs/ntfs3/index.c:838
 indx_insert_into_buffer+0x1b6/0x2010 fs/ntfs3/index.c:1815
 indx_insert_entry+0xcde/0x1050 fs/ntfs3/index.c:1997
 ni_add_name+0xef7/0x11e0 fs/ntfs3/frecord.c:2931
 ni_rename+0x97/0x220 fs/ntfs3/frecord.c:2962
 ntfs_rename+0xdd2/0x1290 fs/ntfs3/namei.c:332
 vfs_rename+0x249d/0x29a0 fs/namei.c:5938
 do_renameat2+0xb7f/0x15a0 fs/namei.c:6056
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0xd7/0x140 fs/namei.c:6097
 x64_sys_call+0x2c5/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4960 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_noprof+0x967/0x1730 mm/slub.c:5270
 ntfs_rename+0x874/0x1290 fs/ntfs3/namei.c:307
 vfs_rename+0x249d/0x29a0 fs/namei.c:5938
 do_renameat2+0xb7f/0x15a0 fs/namei.c:6056
 __do_sys_rename fs/namei.c:6099 [inline]
 __se_sys_rename fs/namei.c:6097 [inline]
 __x64_sys_rename+0xd7/0x140 fs/namei.c:6097
 x64_sys_call+0x2c5/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 5785 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(voluntary) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
=====================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/30 14:11 upstream 4d310797262f bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_read_hdr
2026/01/28 14:34 upstream 1f97d9dcf536 004c195c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_read_hdr
2026/01/15 21:45 upstream 944aacb68baf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_read_hdr
* Struck through repros no longer work on HEAD.