CVE-2025-68242

Summary

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

NFS: Fix LTP test failures when timestamps are delegated

The utimes01 and utime06 tests fail when delegated timestamps are enabled, specifically in subtests that modify the atime and mtime fields using the 'nobody' user ID.

The problem can be reproduced as follow:

echo "/media *(rw,no_root_squash,sync)" >> /etc/exports

export -ra

mount -o rw,nfsvers=4.2 127.0.0.1:/media /tmpdir

cd /opt/ltp

./runltp -d /tmpdir -s utimes01

./runltp -d /tmpdir -s utime06

This issue occurs because nfs_setattr does not verify the inode's UID against the caller's fsuid when delegated timestamps are permitted for the inode.

This patch adds the UID check and if it does not match then the request is sent to the server for permission checking.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe12912d94137ab36ee704a91f465ff15c8b423da < b2e4cda71ed062c87573b016d2d956a62f4258edaffected
LinuxLinuxe12912d94137ab36ee704a91f465ff15c8b423da < 0e9be902041c6b9f0ed4b72764187eed1067a42faffected
LinuxLinuxe12912d94137ab36ee704a91f465ff15c8b423da < b623390045a81fc559decb9bfeb79319721d3dfbaffected
LinuxLinux6.11affected
LinuxLinux0 < 6.11unaffected
LinuxLinux6.12.59 <= 6.12.*unaffected
LinuxLinux6.17.9 <= 6.17.*unaffected
LinuxLinux6.18 <= *unaffected

Weaknesses

References