5.5

CVE-2026-53029

fs/ntfs3: prevent uninitialized lcn caused by zero len

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: prevent uninitialized lcn caused by zero len

syzbot reported a uninit-value in ntfs_iomap_begin [1].

Since runs was not touched yet, run_lookup_entry() immediately fails
and returns false, which makes the value of "*len" 0.
Simultaneously, the new value and err value are also 0, causing the
logic in attr_data_get_block_locked() to jump directly to ok, ultimately
resulting in *lcn being triggered before it is set [1].

In ntfs_iomap_begin(), the check for a 0 value in clen is moved forward
to before updating lcn to avoid this [1].

[1]
BUG: KMSAN: uninit-value in ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825
 ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825
 iomap_iter+0x9b7/0x1540 fs/iomap/iter.c:110

Local variable lcn created at:
 ntfs_iomap_begin+0x15d/0x1460 fs/ntfs3/inode.c:786
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 7.0 < 7.0.10
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.11% 0.014
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 5.5 1.8 3.6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-908 Use of Uninitialized Resource

The product uses or accesses a resource that has not been initialized.

https://git.kernel.org/stable/c/485f750cac3d8bdf5552a0e3d79ce5e3a03ece49
Patch
https://git.kernel.org/stable/c/e98266e823a1fa06fe6499df61aeaac2fd6f7a49
Patch