# CVE-2026-63878: drm/amdgpu: check num\_entries in GEM\_OP GET\_MAPPING\_INFO

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-07-19 · Updated: 2026-07-19

## Affected

- Linux: version range not reported
- Linux: 6.18

## Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: check num_entries in GEM_OP GET_MAPPING_INFO kvcalloc(args->num_entries, sizeof(*vm_entries), GFP_KERNEL) at amdgpu_gem.c:1050 uses the user-supplied num_entries directly without any upper bounds check. Since num_entries is a __u32 and sizeof(drm_amdgpu_gem_vm_entry) is 32 bytes, a large num_entries produces an allocation exceeding INT_MAX, triggering WARNING in __kvmalloc_node_noprof(), causing a kernel WARNING, TAINT_WARN, and panic on CONFIG_PANIC_ON_WARN=y systems. Add a size bounds check before we invoke the kvzalloc() to reject oversized num_entries early with -EINVAL. (cherry picked from commit 1fe7bf5457f6efd7be60b17e23163ba54341d73d)

## 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.
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## 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/f059b4c493df3e54fe3ffe4658009c31864275da
- https://git.kernel.org/stable/c/967a00b8e06a7734aded23861faba9ee2462be87
- https://git.kernel.org/stable/c/a1ba4594232c87c3b8defd6f89a2e40f8b08395d

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