CVE-2024-38662 bpf: Allow delete from sockmap/sockhash only if update is allowed

2024-06-2111:15:12

Linux

github.com

linux kernel

vulnerability resolved

bpf program

tracepoint

locking rule violation

map_delete

verifier

allowed-program-type check

updating map

deletion restriction

security fix

cve-2024-38662

6.9 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

10.0%

JSON

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

bpf: Allow delete from sockmap/sockhash only if update is allowed

We have seen an influx of syzkaller reports where a BPF program attached to
a tracepoint triggers a locking rule violation by performing a map_delete
on a sockmap/sockhash.

We don’t intend to support this artificial use scenario. Extend the
existing verifier allowed-program-type check for updating sockmap/sockhash
to also cover deleting from a map.

From now on only BPF programs which were previously allowed to update
sockmap/sockhash can delete from these map types.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "dd54b48db0c8",
        "lessThan": "29467edc2381",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "d1e73fb19a4c",
        "lessThan": "11e8ecc5b860",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a44770fed865",
        "lessThan": "6693b172f008",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "668b3074aa14",
        "lessThan": "000a65bf1dc0",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ff9105993240",
        "lessThan": "b81e1c5a3c70",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ff9105993240",
        "lessThan": "98e948fb60d4",
        "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": "6.9"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "6.9",
        "versionType": "custom"
      },
      {
        "status": "unaffected",
        "version": "5.10.219",
        "versionType": "custom",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.15.161",
        "versionType": "custom",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "6.1.93",
        "versionType": "custom",
        "lessThanOrEqual": "6.1.*"
      },
      {
        "status": "unaffected",
        "version": "6.6.33",
        "versionType": "custom",
        "lessThanOrEqual": "6.6.*"
      },
      {
        "status": "unaffected",
        "version": "6.9.4",
        "versionType": "custom",
        "lessThanOrEqual": "6.9.*"
      },
      {
        "status": "unaffected",
        "version": "6.10-rc2",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "kernel/bpf/verifier.c"
    ],
    "defaultStatus": "affected"
  }
]