Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 88b88a66797159949cec32eaab12b4968f6fae2d before 700f3a7c7fa5764c9f24bbf7c78e0b6e479fa653; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 4ce87674c3a6b4d3b3d45f85b584ab8618a3cece; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 000bab8753ae29a259feb339b99ee759795a48ac; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 88ff021e1fea2d9b40b2d5efd9013c89f7be04ac; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 32f348ecc149e9ca70a1c424ae8fa9b6919d2713; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 5e0de753bfe87768ebe6744d869caa92f35e5731; affected 88b88a66797159949cec32eaab12b4968f6fae2d before f3bfac2cabf5333506b263bc0c8497c95302f32d; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 4583290898c13c2c2e5eb8773886d153c2c5121d; affected 88b88a66797159949cec32eaab12b4968f6fae2d before 4f5a100f87f32cb65d4bb1ad282a08c92f6f591e |
| Linux / Linux | affected 3.18; unaffected 0 before 3.18; unaffected 4.19.323 through 4.19.*; unaffected 5.4.285 through 5.4.*; unaffected 5.10.227 through 5.10.*; unaffected 5.15.168 through 5.15.*; unaffected 6.1.113 through 6.1.*; unaffected 6.6.54 through 6.6.*; unaffected 6.10.13 through 6.10.*; unaffected 6.11.2 through 6.11.*; unaffected 6.12 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/700f3a7c7fa5764c9f24bbf7c78e0b6e479fa653
- https://git.kernel.org/stable/c/4ce87674c3a6b4d3b3d45f85b584ab8618a3cece
- https://git.kernel.org/stable/c/000bab8753ae29a259feb339b99ee759795a48ac
- https://git.kernel.org/stable/c/88ff021e1fea2d9b40b2d5efd9013c89f7be04ac
- https://git.kernel.org/stable/c/32f348ecc149e9ca70a1c424ae8fa9b6919d2713
- https://git.kernel.org/stable/c/5e0de753bfe87768ebe6744d869caa92f35e5731
- https://git.kernel.org/stable/c/f3bfac2cabf5333506b263bc0c8497c95302f32d
- https://git.kernel.org/stable/c/4583290898c13c2c2e5eb8773886d153c2c5121d
- https://git.kernel.org/stable/c/4f5a100f87f32cb65d4bb1ad282a08c92f6f591e
ADP enrichment
No English description supplied.
No references supplied.
No English description supplied.