efi: stmm: Fix incorrect buffer allocation method
In the Linux kernel, the following vulnerability has been resolved: efi: stmm: Fix incorrect buffer allocation method The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well. Fix this by using alloc_pages_exact() instead of kmalloc().
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: efi: stmm: Fix incorrect buffer allocation method The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well. Fix this by using alloc_pages_exact() instead of kmalloc().
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/630c0e6064daf84f17aad1a7d9ca76b562e3fe47
- https://git.kernel.org/stable/c/77ff27ff0e4529a003c8a1c2492c111968c378d3
- https://git.kernel.org/stable/c/c5e81e672699e0c5557b2b755cc8f7a69aa92bff
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39836.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-39836