# CVE-2026-46250: MIPS: Work around LLVM bug when gp is used as global register variable

> A bug in LLVM handling of MIPS global register variables causes the kernel to crash during boot due to an invalid pointer dereference.

- **Severity:** High 7.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Jun 2026
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-89339, BELL-CVE-2026-46250, DEBIAN-CVE-2026-46250, GHSA-9x8g-p3w8-2v5p, ROOT-OS-UBUNTU-2204-CVE-2026-46250, UBUNTU-CVE-2026-46250

## What is CVE-2026-46250?

CVE-2026-46250 is a high-severity vulnerability in Linux kernel, published on 3 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

MIPS: Work around LLVM bug when gp is used as global register variable

On MIPS, __current_thread_info is defined as global register variable
locating in $gp, and is simply assigned with new address during kernel
relocation.

This however is broken with LLVM, which always restores $gp if it finds
$gp is clobbered in any form, including when intentionally through a
global register variable. This is against GCC's documentation[1], which
requires a callee-saved register used as global register variable not to
be restored if it's clobbered.

As a result, $gp will continue to point to the unrelocated kernel after
the epilog of relocate_kernel(), leading to an early crash in init_idle,

[    0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff81afada8, ra == ffffffff81afad90
[    0.000000] Oops[#1]:
[    0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Tainted: G        W           6.19.0-rc5-00262-gd3eeb99bbc99-dirty #188 VOLUNTARY
[    0.000000] Tainted: [W]=WARN
[    0.000000] Hardware name: loongson,loongson64v-4core-virtio
[    0.000000] $ 0   : 0000000000000000 0000000000000000 0000000000000001 0000000000000000
[    0.000000] $ 4   : ffffffff80b80ec0 ffffffff80b53d48 0000000000000000 00000000000f4240
[    0.000000] $ 8   : 0000000000000100 ffffffff81d82f80 ffffffff81d82f80 0000000000000001
[    0.000000] $12   : 0000000000000000 ffffffff81776f58 00000000000005da 0000000000000002
[    0.000000] $16   : ffffffff80b80e40 0000000000000000 ffffffff80b81614 9800000005dfbe80
[    0.000000] $20   : 00000000540000e0 ffffffff81980000 0000000000000000 ffffffff80f81c80
[    0.000000] $24   : 0000000000000a26 ffffffff8114fb90
[    0.000000] $28   : ffffffff80b50000 ffffffff80b53d40 0000000000000000 ffffffff81afad90
[    0.000000] Hi    : 0000000000000000
[    0.000000] Lo    : 0000000000000000
[    0.000000] epc   : ffffffff81afada8 init_idle+0x130/0x270
[    0.000000] ra    : ffffffff81afad90 init_idle+0x118/0x270
[    0.000000] Status: 540000e2	KX SX UX KERNEL EXL
[    0.000000] Cause : 00000008 (ExcCode 02)
[    0.000000] BadVA : 0000000000000000
[    0.000000] PrId  : 00006305 (ICT Loongson-3)
[    0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
[    0.000000] Stack : 9800000005dfbf00 ffffffff8178e950 0000000000000000 0000000000000000
[    0.000000]         0000000000000000 ffffffff81970000 000000000000003f ffffffff810a6528
[    0.000000]         0000000000000001 9800000005dfbe80 9800000005dfbf00 ffffffff81980000
[    0.000000]         ffffffff810a6450 ffffffff81afb6c0 0000000000000000 ffffffff810a2258
[    0.000000]         ffffffff81d82ec8 ffffffff8198d010 ffffffff81b67e80 ffffffff8197dd98
[    0.000000]         ffffffff81d81c80 ffffffff81930000 0000000000000040 0000000000000000
[    0.000000]         0000000000000000 0000000000000000 0000000000000000 0000000000000000
[    0.000000]         0000000000000000 000000000000009e ffffffff9fc01000 0000000000000000
[    0.000000]         0000000000000000 0000000000000000 0000000000000000 0000000000000000
[    0.000000]         0000000000000000 ffffffff81ae86dc ffffffff81b3c741 0000000000000002
[    0.000000]         ...
[    0.000000] Call Trace:
[    0.000000] [<ffffffff81afada8>] init_idle+0x130/0x270
[    0.000000] [<ffffffff81afb6c0>] sched_init+0x5c8/0x6c0
[    0.000000] [<ffffffff81ae86dc>] start_kernel+0x27c/0x7a8

This bug has been reported to LLVM[2] and affects version from (at
least) 18 to 21. Let's work around this by using inline assembly to
assign $gp before a fix is widely available.

## Which versions are affected by CVE-2026-46250?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46250?

Apply the vendor's patch.

## Is CVE-2026-46250 being exploited?

There is no known exploitation of CVE-2026-46250 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-46250 and fix it if it is affected.

What it is: CVE-2026-46250 is a high-severity vulnerability in Linux kernel, published on 3 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-46250 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-46250/ (Markdown: https://insights.sbomify.com/CVE-2026-46250/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46250
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46250
- OSV: https://osv.dev/vulnerability/CVE-2026-46250

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46250/
Summaries are generated and may contain mistakes; the official description above is the record.
