CVE-2024-38576 rcu: Fix buffer overflow in print_cpu_stall_info()

2024-06-1913:37:35

Linux

www.cve.org

linux kernel

buffer overflow

rcu

print_cpu_stall_info

vulnerability

fix

linux verification center

svace

EPSS

Percentile

15.5%

JSON

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

rcu: Fix buffer overflow in print_cpu_stall_info()

The rcuc-starvation output from print_cpu_stall_info() might overflow the
buffer if there is a huge difference in jiffies difference. The situation
might seem improbable, but computers sometimes get very confused about
time, which can result in full-sized integers, and, in this case,
buffer overflow.

Also, the unsigned jiffies difference is printed using %ld, which is
normally for signed integers. This is intentional for debugging purposes,
but it is not obvious from the code.

This commit therefore changes sprintf() to snprintf() and adds a
clarifying comment about intention of %ld format.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "kernel/rcu/tree_stall.h"
    ],
    "versions": [
      {
        "version": "245a62982502",
        "lessThan": "e2228ed3fe7a",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "245a62982502",
        "lessThan": "afb39909bfb5",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "245a62982502",
        "lessThan": "9351e1338539",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "245a62982502",
        "lessThan": "4c3e2ef4d8dd",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "245a62982502",
        "lessThan": "3758f7d9917b",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "kernel/rcu/tree_stall.h"
    ],
    "versions": [
      {
        "version": "6.0",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.0",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.93",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.33",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8.12",
        "lessThanOrEqual": "6.8.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9.3",
        "lessThanOrEqual": "6.9.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.10",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]