KMSAN: uninit-value in ntfs_iomap_begin (2)

Status: upstream: reported on 2026/06/29 19:21
Subsystems: ntfs3
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+4b4ec878e25fafefa70f@syzkaller.appspotmail.com
First crash: 56d, last: 3d10h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
d181d195 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ KMSAN: uninit-value in ntfs_iomap_begin (2) 2026/06/27 01:51 2026/06/27 01:51 2026/06/27 02:32 7ff32d8b
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly ntfs3 report (Aug 2026) 0 (1) 2026/08/04 12:32
[PATCH] ntfs3: reject empty iomap before reading its LCN 1 (1) 2026/06/30 21:17
[syzbot] [ntfs3?] KMSAN: uninit-value in ntfs_iomap_begin (2) 0 (1) 2026/06/29 19:21
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in ntfs_iomap_begin ntfs3 prio:high 7 syz, C 191 128d 179d 29/29 fixed on 2026/05/21 07:50

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in ntfs_iomap_begin+0x8a3/0x1550 fs/ntfs3/inode.c:778
 ntfs_iomap_begin+0x8a3/0x1550 fs/ntfs3/inode.c:778
 iomap_iter+0x9d9/0x14f0 fs/iomap/iter.c:110
 iomap_read_folio+0x691/0xb40 fs/iomap/buffered-io.c:669
 ntfs_read_folio+0x74f/0x770 fs/ntfs3/inode.c:649
 filemap_read_folio mm/filemap.c:2516 [inline]
 do_read_cache_folio+0x96d/0x13d0 mm/filemap.c:4146
 do_read_cache_page mm/filemap.c:4212 [inline]
 read_cache_page+0x63/0x1e0 mm/filemap.c:4221
 read_mapping_page include/linux/pagemap.h:1009 [inline]
 inode_read_data+0xbb/0x560 fs/ntfs3/inode.c:1055
 ntfs_fill_super+0x720c/0x8820 fs/ntfs3/super.c:1582
 get_tree_bdev_flags+0x6ef/0x930 fs/super.c:1640
 get_tree_bdev+0x38/0x50 fs/super.c:1663
 ntfs_fs_get_tree+0x35/0x40 fs/ntfs3/super.c:1819
 vfs_get_tree+0xae/0x5d0 fs/super.c:1700
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x885/0x1dc0 fs/namespace.c:3841
 path_mount+0x7a2/0x20a0 fs/namespace.c:4161
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount+0x704/0x7f0 fs/namespace.c:4367
 __x64_sys_mount+0xed/0x180 fs/namespace.c:4367
 x64_sys_call+0x39f0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15d/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable lcn created at:
 ntfs_iomap_begin+0x157/0x1550 fs/ntfs3/inode.c:739
 iomap_iter+0x9d9/0x14f0 fs/iomap/iter.c:110

CPU: 0 UID: 0 PID: 6972 Comm: syz.0.546 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
=====================================================

Crashes (112):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/17 18:02 upstream a59f57e2aa12 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/14 18:51 upstream a59f57e2aa12 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/14 17:29 upstream a59f57e2aa12 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/14 06:19 upstream a59f57e2aa12 b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/13 16:48 upstream a59f57e2aa12 a9ede23c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/13 09:30 upstream a59f57e2aa12 67796a05 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/13 07:25 upstream a59f57e2aa12 67796a05 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/12 17:58 upstream a59f57e2aa12 7ae4acc7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/12 04:00 upstream a59f57e2aa12 f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/11 11:55 upstream a59f57e2aa12 37a258dd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/10 20:15 upstream a59f57e2aa12 039457bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/08 23:45 upstream a59f57e2aa12 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/07 17:35 upstream fc02acf6ac0c e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/07 15:06 upstream fc02acf6ac0c e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/06 22:24 upstream fc02acf6ac0c c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/06 21:14 upstream fc02acf6ac0c c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/05 23:05 upstream fc02acf6ac0c cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/05 09:40 upstream fc02acf6ac0c b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/05 08:24 upstream fc02acf6ac0c b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/04 21:38 upstream fc02acf6ac0c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/04 04:11 upstream fc02acf6ac0c a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/04 03:03 upstream fc02acf6ac0c a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/08/01 20:06 upstream fc02acf6ac0c e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/31 21:03 upstream fc02acf6ac0c 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/31 19:52 upstream fc02acf6ac0c 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/31 03:59 upstream fc02acf6ac0c aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/31 02:46 upstream fc02acf6ac0c aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/30 10:41 upstream fc02acf6ac0c 2377cd3d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/29 20:29 upstream fc02acf6ac0c cb1587ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/29 18:40 upstream fc02acf6ac0c cb1587ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/29 11:09 upstream fc02acf6ac0c 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/29 08:29 upstream fc02acf6ac0c 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/28 22:18 upstream 4a50a141f05a 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/28 18:44 upstream 4a50a141f05a 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/27 18:14 upstream 4a50a141f05a 4cb2b096 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/26 05:09 upstream 4a50a141f05a 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/24 19:16 upstream 4a50a141f05a 05b26a28 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/24 17:53 upstream 4a50a141f05a 05b26a28 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/24 12:22 upstream 4a50a141f05a 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/23 17:38 upstream 4a50a141f05a 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/23 11:58 upstream 4a50a141f05a 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/22 20:22 upstream 4a50a141f05a 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/06/29 16:40 upstream 962528fef902 6a0c72dc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/06/27 00:00 upstream 962528fef902 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/06/25 19:14 upstream 962528fef902 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in ntfs_iomap_begin
2026/07/12 22:47 upstream 665159e24674 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in ntfs_iomap_begin
* Struck through repros no longer work on HEAD.