In the Linux kernel, the following vulnerability has been resolved:
drm/shmem-helper: Fix BUGON() on mmap(PROTWRITE, MAP_PRIVATE)
Lack of check for copy-on-write (COW) mapping in drmgemshmemmmap allows users to call mmap with PROTWRITE and MAPPRIVATE flag causing a kernel panic due to BUGON in vmfinsertpfnprot: BUGON((vma->vmflags & VMPFNMAP) && iscowmapping(vma->vm_flags));
Return -EINVAL early if COW mapping is detected.
This bug affects all drm drivers using default shmem helpers. It can be reproduced by this simple example: void *ptr = mmap(0, size, PROTWRITE, MAPPRIVATE, fd, mmap_offset); ptr[0] = 0;
{
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/39xxx/CVE-2024-39497.json"
}