{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Fix READDIR buffer overflow\n\nIf a client sends a READDIR count argument that is too small (say,\nzero), then the buffer size calculation in the new init_dirlist\nhelper functions results in an underflow, allowing the XDR stream\nfunctions to write beyond the actual buffer.\n\nThis calculation has always been suspect. NFSD has never sanity-\nchecked the READDIR count argument, but the old entry encoders\nmanaged the problem correctly.\n\nWith the commits below, entry encoding changed, exposing the\nunderflow to the pointer arithmetic in xdr_reserve_space().\n\nModern NFS clients attempt to retrieve as much data as possible\nfor each READDIR request. Also, we have no unit tests that\nexercise the behavior of READDIR at the lower bound of @count\nvalues. Thus this case was missed during testing."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "fs/nfsd/nfs3proc.c",
                  "fs/nfsd/nfsproc.c"
               ],
               "versions": [
                  {
                     "version": "37aa5e640222",
                     "lessThan": "9e291a6a28d3",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "7f87fc2d34d4",
                     "lessThan": "eabc0aab98e5",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "7f87fc2d34d4",
                     "lessThan": "53b1119a6e50",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "fs/nfsd/nfs3proc.c",
                  "fs/nfsd/nfsproc.c"
               ],
               "versions": [
                  {
                     "version": "5.13",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.13",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.12",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.16",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/9e291a6a28d32545ed2fd959a8165144d1724df1"
            },
            {
               "url": "https://git.kernel.org/stable/c/eabc0aab98e5218ceecd82069b0d6fdfff5ee885"
            },
            {
               "url": "https://git.kernel.org/stable/c/53b1119a6e5028b125f431a0116ba73510d82a72"
            }
         ],
         "title": "NFSD: Fix READDIR buffer overflow",
         "x_generator": {
            "engine": "bippy-7d53e8ef8be4"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47107",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}