{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: Only allow init netns to set default tcp cong to a restricted algo\n\ntcp_set_default_congestion_control() is netns-safe in that it writes\nto &net->ipv4.tcp_congestion_control, but it also sets\nca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced.\nThis has the unintended side-effect of changing the global\nnet.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it\nis read-only: 97684f0970f6 (\"net: Make tcp_allowed_congestion_control\nreadonly in non-init netns\")\n\nResolve this netns \"leak\" by only allowing the init netns to set the\ndefault algorithm to one that is restricted. This restriction could be\nremoved if tcp_allowed_congestion_control were namespace-ified in the\nfuture.\n\nThis bug was uncovered with\nhttps://github.com/JonathonReinhart/linux-netns-sysctl-verify"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "net/ipv4/tcp_cong.c"
               ],
               "versions": [
                  {
                     "version": "6670e1524477",
                     "lessThan": "992de06308d9",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "6670e1524477",
                     "lessThan": "9884f745108f",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "6670e1524477",
                     "lessThan": "6c1ea8bee75d",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "6670e1524477",
                     "lessThan": "efe1532a6e1a",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "6670e1524477",
                     "lessThan": "e7d7bedd507b",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "6670e1524477",
                     "lessThan": "8d432592f30f",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "net/ipv4/tcp_cong.c"
               ],
               "versions": [
                  {
                     "version": "4.15",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "4.15",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "4.19.191",
                     "lessThanOrEqual": "4.19.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.4.119",
                     "lessThanOrEqual": "5.4.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.37",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.11.21",
                     "lessThanOrEqual": "5.11.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.12.4",
                     "lessThanOrEqual": "5.12.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.13",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/992de06308d9a9584d59b96d294ac676f924e437"
            },
            {
               "url": "https://git.kernel.org/stable/c/9884f745108f7d25b189bbcd6754e284fb29ab68"
            },
            {
               "url": "https://git.kernel.org/stable/c/6c1ea8bee75df8fe2184a50fcd0f70bf82986f42"
            },
            {
               "url": "https://git.kernel.org/stable/c/efe1532a6e1a8e3c343d04fff510f0ed80328f9c"
            },
            {
               "url": "https://git.kernel.org/stable/c/e7d7bedd507bb732e600403b7a96f9fe48d0ca31"
            },
            {
               "url": "https://git.kernel.org/stable/c/8d432592f30fcc34ef5a10aac4887b4897884493"
            }
         ],
         "title": "net: Only allow init netns to set default tcp cong to a restricted algo",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47010",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}