cve/published/2021/CVE-2021-47125.json

{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsch_htb: fix refcount leak in htb_parent_to_leaf_offload\n\nThe commit ae81feb7338c (\"sch_htb: fix null pointer dereference\non a null new_q\") fixes a NULL pointer dereference bug, but it\nis not correct.\n\nBecause htb_graft_helper properly handles the case when new_q\nis NULL, and after the previous patch by skipping this call\nwhich creates an inconsistency : dev_queue->qdisc will still\npoint to the old qdisc, but cl->parent->leaf.q will point to\nthe new one (which will be noop_qdisc, because new_q was NULL).\nThe code is based on an assumption that these two pointers are\nthe same, so it can lead to refcount leaks.\n\nThe correct fix is to add a NULL pointer check to protect\nqdisc_refcount_inc inside htb_parent_to_leaf_offload."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "net/sched/sch_htb.c"
               ],
               "versions": [
                  {
                     "version": "ae81feb7338c89cee4e6aa0424bdab2ce2b52da2",
                     "lessThan": "2411c02d03892a5057499f8102d0cc1e0f852416",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "ae81feb7338c89cee4e6aa0424bdab2ce2b52da2",
                     "lessThan": "944d671d5faa0d78980a3da5c0f04960ef1ad893",
                     "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/sched/sch_htb.c"
               ],
               "versions": [
                  {
                     "version": "5.12",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.12",
                     "status": "unaffected",
                     "versionType": "semver"
                  },
                  {
                     "version": "5.12.10",
                     "lessThanOrEqual": "5.12.*",
                     "status": "unaffected",
                     "versionType": "semver"
                  },
                  {
                     "version": "5.13",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "cpeApplicability": [
            {
               "nodes": [
                  {
                     "operator": "OR",
                     "negate": false,
                     "cpeMatch": [
                        {
                           "vulnerable": true,
                           "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                           "versionStartIncluding": "5.12",
                           "versionEndExcluding": "5.12.10"
                        },
                        {
                           "vulnerable": true,
                           "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                           "versionStartIncluding": "5.12",
                           "versionEndExcluding": "5.13"
                        }
                     ]
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/2411c02d03892a5057499f8102d0cc1e0f852416"
            },
            {
               "url": "https://git.kernel.org/stable/c/944d671d5faa0d78980a3da5c0f04960ef1ad893"
            }
         ],
         "title": "sch_htb: fix refcount leak in htb_parent_to_leaf_offload",
         "x_generator": {
            "engine": "bippy-1.2.0"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47125",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}