CVE-2023-52462 bpf: fix check for attempt to corrupt spilled pointer

2024-02-2314:46:22

Linux

github.com

linux kernel

bpf

vulnerability

AI Score

7.1

Confidence

Low

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

bpf: fix check for attempt to corrupt spilled pointer

When register is spilled onto a stack as a 1/2/4-byte register, we set
slot_type[BPF_REG_SIZE - 1] (plus potentially few more below it,
depending on actual spill size). So to check if some stack slot has
spilled register we need to consult slot_type[7], not slot_type[0].

To avoid the need to remember and double-check this in the future, just
use is_spilled_reg() helper.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "cdd73a5ed084",
        "lessThan": "2757f17972d8",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "07c286c10a9c",
        "lessThan": "67e6707f0735",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "27113c59b6d0",
        "lessThan": "fc3e3c50a0a4",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "27113c59b6d0",
        "lessThan": "8dc15b067059",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "27113c59b6d0",
        "lessThan": "40617d45ea05",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "27113c59b6d0",
        "lessThan": "ab125ed3ec1c",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "kernel/bpf/verifier.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "5.16"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "5.16",
        "versionType": "custom"
      },
      {
        "status": "unaffected",
        "version": "5.10.209",
        "versionType": "custom",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.15.148",
        "versionType": "custom",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "6.1.75",
        "versionType": "custom",
        "lessThanOrEqual": "6.1.*"
      },
      {
        "status": "unaffected",
        "version": "6.6.14",
        "versionType": "custom",
        "lessThanOrEqual": "6.6.*"
      },
      {
        "status": "unaffected",
        "version": "6.7.2",
        "versionType": "custom",
        "lessThanOrEqual": "6.7.*"
      },
      {
        "status": "unaffected",
        "version": "6.8",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "kernel/bpf/verifier.c"
    ],
    "defaultStatus": "affected"
  }
]