CVE-2024-26720

2024-04-0315:15:53

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

web.nvd.nist.gov

linux kernel

writeback

vulnerability

memory management

security

6.1 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

12.9%

JSON

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

mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again

(struct dirty_throttle_control *)->thresh is an unsigned long, but is
passed as the u32 divisor argument to div_u64(). On architectures where
unsigned long is 64 bytes, the argument will be implicitly truncated.

Use div64_u64() instead of div_u64() so that the value used in the “is
this a safe division” check is the same as the divisor.

Also, remove redundant cast of the numerator to u64, as that should happen
implicitly.

This would be difficult to exploit in memcg domain, given the ratio-based
arithmetic domain_drity_limits() uses, but is much easier in global
writeback domain with a BDI_CAP_STRICTLIMIT-backing device, using e.g.
vm.dirty_bytes=(1<<32)*PAGE_SIZE so that dtc->thresh == (1<<32)

Affected configurations

Vulners

Node

linuxlinux_kernelRange3.16–4.19.307

linuxlinux_kernelRange4.20.0–5.4.269

linuxlinux_kernelRange5.5.0–5.10.210

linuxlinux_kernelRange5.11.0–5.15.149

linuxlinux_kernelRange5.16.0–6.1.79

linuxlinux_kernelRange6.2.0–6.6.18

linuxlinux_kernelRange6.7.0–6.7.6

linuxlinux_kernelRange6.8.0≥

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

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
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": [
      "mm/page-writeback.c"
    ],
    "versions": [
      {
        "version": "f6789593d5ce",
        "lessThan": "c593d26fb5d5",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "1f12e4b3284d",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "81e7d2530d45",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "5099871b3703",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "16b1025eaa8f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "ec18ec230301",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "65977bed167a",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "f6789593d5ce",
        "lessThan": "9319b647902c",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "mm/page-writeback.c"
    ],
    "versions": [
      {
        "version": "3.16",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "3.16",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.19.307",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.269",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.210",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.149",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.79",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.18",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.6",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]