{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/fair: Fix fault in reweight_entity\n\nSyzbot found a GPF in reweight_entity. This has been bisected to\ncommit 4ef0c5c6b5ba (\"kernel/sched: Fix sched_fork() access an invalid\nsched_task_group\")\n\nThere is a race between sched_post_fork() and setpriority(PRIO_PGRP)\nwithin a thread group that causes a null-ptr-deref in\nreweight_entity() in CFS. The scenario is that the main process spawns\nnumber of new threads, which then call setpriority(PRIO_PGRP, 0, -20),\nwait, and exit.  For each of the new threads the copy_process() gets\ninvoked, which adds the new task_struct and calls sched_post_fork()\nfor it.\n\nIn the above scenario there is a possibility that\nsetpriority(PRIO_PGRP) and set_one_prio() will be called for a thread\nin the group that is just being created by copy_process(), and for\nwhich the sched_post_fork() has not been executed yet. This will\ntrigger a null pointer dereference in reweight_entity(), as it will\ntry to access the run queue pointer, which hasn't been set.\n\nBefore the mentioned change the cfs_rq pointer for the task  has been\nset in sched_fork(), which is called much earlier in copy_process(),\nbefore the new task is added to the thread_group.  Now it is done in\nthe sched_post_fork(), which is called after that.  To fix the issue\nthe remove the update_load param from the update_load param() function\nand call reweight_task() only if the task flag doesn't have the\nTASK_NEW flag set."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "kernel/sched/core.c"
               ],
               "versions": [
                  {
                     "version": "c85c6fadbef0",
                     "lessThan": "8f317cd88805",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "3869eecf0504",
                     "lessThan": "e0bcd6b57793",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "4ef0c5c6b5ba",
                     "lessThan": "589a954daab5",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "4ef0c5c6b5ba",
                     "lessThan": "13765de8148f",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "kernel/sched/core.c"
               ],
               "versions": [
                  {
                     "version": "5.16",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.16",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.137",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.27",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.16.13",
                     "lessThanOrEqual": "5.16.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.17",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/8f317cd888059c59e2fa924bf4b0957cfa53f78e"
            },
            {
               "url": "https://git.kernel.org/stable/c/e0bcd6b5779352aed88f2e538a82a39f1a7715bb"
            },
            {
               "url": "https://git.kernel.org/stable/c/589a954daab5e18399860b6c8ffaeaf79844eb20"
            },
            {
               "url": "https://git.kernel.org/stable/c/13765de8148f71fa795e0a6607de37c49ea5915a"
            }
         ],
         "title": "sched/fair: Fix fault in reweight_entity",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2022-48921",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}