CVE-2024-39497

2024-07-1213:15:12

Linux

web.nvd.nist.gov

linux kernel

vulnerability resolved

drm/shmem-helper

cow mapping

mmap

prot_write

map_private

kernel panic

AI Score

6.4

Confidence

Low

EPSS

Percentile

15.9%

JSON

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

drm/shmem-helper: Fix BUG_ON() on mmap(PROT_WRITE, MAP_PRIVATE)

Lack of check for copy-on-write (COW) mapping in drm_gem_shmem_mmap
allows users to call mmap with PROT_WRITE and MAP_PRIVATE flag
causing a kernel panic due to BUG_ON in vmf_insert_pfn_prot:
BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(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, PROT_WRITE, MAP_PRIVATE, fd, mmap_offset);
ptr[0] = 0;

Affected configurations

Vulners

Node

linuxlinux_kernelRange5.2–6.6.35

linuxlinux_kernelRange6.7.0–6.9.6

linuxlinux_kernelRange6.10.0≥

VendorProductVersionCPE
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/gpu/drm/drm_gem_shmem_helper.c"
    ],
    "versions": [
      {
        "version": "2194a63a818d",
        "lessThan": "1b4a8b89bf67",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "2194a63a818d",
        "lessThan": "03c71c42809e",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "2194a63a818d",
        "lessThan": "39bc27bd6880",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/gpu/drm/drm_gem_shmem_helper.c"
    ],
    "versions": [
      {
        "version": "5.2",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.2",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.35",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9.6",
        "lessThanOrEqual": "6.9.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.10",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]