CVE-2026-98540

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: fprobe: Terminate the fgraph_data list when the reservation is not filled fprobe_fgraph_entry() reserves shadow stack space for every fprobe with an exit handler, but only fills it for those whose entry handler returns 0. fgraph_reserve_data() does not clear the area, so fprobe_return() parses the unused tail as headers left over from an earlier call, and an exit handler can run twice or despite its entry handler asking to skip it. Write a zero word after the last entry to terminate the walk. A zeroed slot does not decode to a NULL fprobe on the arches that encode the header into one unsigned long, since arch_decode_fprobe_header_fp() ORs in FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL for a zeroed slot.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-18 16:17:05.863000

Last modified

2026-10-19 10:19:09.837000

View original CVE JSON

{
  "id": "CVE-2026-98540",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-18T16:17:05.863",
  "lastModified": "2026-10-19T10:19:09.837",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfprobe: Terminate the fgraph_data list when the reservation is not filled\n\nfprobe_fgraph_entry() reserves shadow stack space for every fprobe with\nan exit handler, but only fills it for those whose entry handler returns\n0. fgraph_reserve_data() does not clear the area, so fprobe_return()\nparses the unused tail as headers left over from an earlier call, and an\nexit handler can run twice or despite its entry handler asking to skip\nit.\n\nWrite a zero word after the last entry to terminate the walk. A zeroed\nslot does not decode to a NULL fprobe on the arches that encode the\nheader into one unsigned long, since arch_decode_fprobe_header_fp() ORs\nin FPROBE_HEADER_MSB_PATTERN, so make read_fprobe_header() return NULL\nfor a zeroed slot."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/trace/fprobe.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "e0a384434ae1bdfb03954c46c464e3dbd3223ad6",
              "lessThan": "b7459fddcb27a4b7d01067678172afa362cf660d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e0a384434ae1bdfb03954c46c464e3dbd3223ad6",
              "lessThan": "1d653a183973f5283a3db5a38cd5e195eb152244",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/trace/fprobe.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.9",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1d653a183973f5283a3db5a38cd5e195eb152244",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b7459fddcb27a4b7d01067678172afa362cf660d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}