CVE-2021-47305 dma-buf/sync_file: Don't leak fences on merge failure

2024-05-2114:35:25

Linux

github.com

linux kernel

vulnerability

dma-buf/sync_file

fence leak

merge failure

AI Score

6.8

Confidence

Low

EPSS

Percentile

10.3%

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

dma-buf/sync_file: Don’t leak fences on merge failure

Each add_fence() call does a dma_fence_get() on the relevant fence. In
the error path, we weren’t calling dma_fence_put() so all those fences
got leaked. Also, in the krealloc_array failure case, we weren’t
freeing the fences array. Instead, ensure that i and fences are always
zero-initialized and dma_fence_put() all the fences and kfree(fences) on
every error path.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "19f51c252933",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "e0355a0ad31a",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "41f45e91c92c",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "0d514185ae79",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "19edcd97727a",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "a02b9dc90d84",
        "lessThan": "ffe000217c50",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "drivers/dma-buf/sync_file.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "4.9"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "4.9",
        "versionType": "custom"
      },
      {
        "status": "unaffected",
        "version": "4.14.241",
        "versionType": "custom",
        "lessThanOrEqual": "4.14.*"
      },
      {
        "status": "unaffected",
        "version": "4.19.199",
        "versionType": "custom",
        "lessThanOrEqual": "4.19.*"
      },
      {
        "status": "unaffected",
        "version": "5.4.135",
        "versionType": "custom",
        "lessThanOrEqual": "5.4.*"
      },
      {
        "status": "unaffected",
        "version": "5.10.53",
        "versionType": "custom",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.13.5",
        "versionType": "custom",
        "lessThanOrEqual": "5.13.*"
      },
      {
        "status": "unaffected",
        "version": "5.14",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "drivers/dma-buf/sync_file.c"
    ],
    "defaultStatus": "affected"
  }
]