vulnerability

Oracle Linux: CVE-2024-47740: ELSA-2024-12884: Unbreakable Enterprise kernel security update (IMPORTANT) (Multiple Advisories)

Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
10/21/2024
Added
12/17/2024
Modified
01/23/2025

Description

In the Linux kernel, the following vulnerability has been resolved:
f2fs: Require FMODE_WRITE for atomic write ioctls
The F2FS ioctls for starting and committing atomic writes check for
inode_owner_or_capable(), but this does not give LSMs like SELinux or
Landlock an opportunity to deny the write access - if the caller's FSUID
matches the inode's UID, inode_owner_or_capable() immediately returns true.
There are scenarios where LSMs want to deny a process the ability to write
particular files, even files that the FSUID of the process owns; but this
can currently partially be bypassed using atomic write ioctls in two ways:
- F2FS_IOC_START_ATOMIC_REPLACE + F2FS_IOC_COMMIT_ATOMIC_WRITE can
truncate an inode to size 0
- F2FS_IOC_START_ATOMIC_WRITE + F2FS_IOC_ABORT_ATOMIC_WRITE can revert
changes another process concurrently made to a file
Fix it by requiring FMODE_WRITE for these operations, just like for
F2FS_IOC_MOVE_RANGE. Since any legitimate caller should only be using these
ioctls when intending to write into the file, that seems unlikely to break
anything.

Solution

oracle-linux-upgrade-kernel-uek
Title
NEW

Explore Exposure Command

Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.