{"id":"CVE-2026-74716","title":"In the Linux kernel, the following vulnerability has been resolved:\n\naccel/amdxdna: Fix locally exploitable BUG_ON in amdxdna_insert_pages()\n\nIn amdxdna_insert_pages(), vm_flags_mod() sets VM_MIXEDMAP and clears\nVM_PFNMAP","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\naccel/amdxdna: Fix locally exploitable BUG_ON in amdxdna_insert_pages()\n\nIn amdxdna_insert_pages(), vm_flags_mod() sets VM_MIXEDMAP and clears\nVM_PFNMAP. If an unprivil…","severity":"none","published":"2026-08-22","updated":"2026-10-14","sourceUpdated":"2026-10-14T13:10:00.187","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74716","references":[{"url":"https://git.kernel.org/stable/c/13339132d89d00b513dff0730bff3a313b9b13b5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4a19f7ab5972ef608b31ae921419bc3e04b3f8ad","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00198,"epssPercentile":0.08868,"ingestedAt":"2026-10-14T13:30:58.546Z","slug":"CVE-2026-74716","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\naccel/amdxdna: Fix locally exploitable BUG_ON in amdxdna_insert_pages()\n\nIn amdxdna_insert_pages(), vm_flags_mod() sets VM_MIXEDMAP and clears\nVM_PFNMAP. If an unprivileged userspace process mmaps a non-imported GEM\nobject and then calls madvise(MADV_DONTNEED), the PTEs will be\nsuccessfully cleared because VM_MIXEDMAP allows this (unlike VM_PFNMAP).\n\nWhen userspace subsequently accesses the memory, drm_gem_shmem_fault()\nhandles the page fault and attempts to map the backing shmem page via\nvmf_insert_pfn() which calls vmf_insert_pfn_prot(). Because the backing\nshmem page is normal system memory (pfn_valid(pfn) is true) and the VMA\nnow has VM_MIXEDMAP set, won't this predictably trigger the explicit\nassertion BUG_ON((vma->vm_flags & VM_MIXEDMAP) && pfn_valid(pfn))\n\nFix by removing the vm_flags_mod() call and replacing the vm_insert_pages()\npre-population with the handle_mm_fault() loop that was already used for\nthe import (dma-buf) path.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}