CVE-2025-38339

MEDIUM
Published Jul 10, 2025 Modified Nov 18, 2025

Description

In the Linux kernel, the following vulnerability has been resolved: powerpc/bpf: fix JIT code size calculation of bpf trampoline arch_bpf_trampoline_size() provides JIT size of the BPF trampoline before the buffer for JIT'ing it is allocated. The total number of instructions emitted for BPF trampoline JIT code depends on where the final image is located. So, the size arrived at with the dummy pass in arch_bpf_trampoline_size() can vary from the actual size needed in arch_prepare_bpf_trampoline(). When the instructions accounted in arch_bpf_trampoline_size() is less than the number of instructions emitted during the actual JIT compile of the trampoline, the below warning is produced: WARNING: CPU: 8 PID: 204190 at arch/powerpc/net/bpf_jit_comp.c:981 __arch_prepare_bpf_trampoline.isra.0+0xd2c/0xdcc which is: /* Make sure the trampoline generation logic doesn't overflow */ if (image && WARN_ON_ONCE(&image[ctx->idx] > (u32 *)rw_image_end - BPF_INSN_SAFETY)) { So, during the dummy pass, instead of providing some arbitrary image location, account for maximum possible instructions if and when there is a dependency with image location for JIT'ing.

Is your site exposed to CVE-2025-38339?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Products

Vendor Product
linux linux_kernel

References

Frequently Asked Questions

What is CVE-2025-38339? +
In the Linux kernel, the following vulnerability has been resolved: powerpc/bpf: fix JIT code size calculation of bpf trampoline arch_bpf_trampoline_size() provides JIT size of the BPF trampoline before the buffer for JIT'ing it is allocated. The total number of instructions emitted for BPF trampoline JIT code depends on where the final image is located. So, the size arrived at with the dummy pass in arch_bpf_trampoline_size() can vary from the actual size needed in arch_prepare_bpf_trampoline(). When the instructions accounted in arch_bpf_trampoline_size() is less than the number of instructions emitted during the actual JIT compile of the trampoline, the below warning is produced: WARNING: CPU: 8 PID: 204190 at arch/powerpc/net/bpf_jit_comp.c:981 __arch_prepare_bpf_trampoline.isra.0+0xd2c/0xdcc which is: /* Make sure the trampoline generation logic doesn't overflow */ if (image && WARN_ON_ONCE(&image[ctx->idx] > (u32 *)rw_image_end - BPF_INSN_SAFETY)) { So, during the dummy pass, instead of providing some arbitrary image location, account for maximum possible instructions if and when there is a dependency with image location for JIT'ing. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2025-38339? +
CVE-2025-38339 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2025-38339? +
CVE-2025-38339 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-38339? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2025-38339 — free, no signup required.