{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2022-48921",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "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\u00a0is a race between sched_post_fork() and setpriority(PRIO_PGRP)\nwithin a thread group that causes a null-ptr-deref\u00a0in\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(),\u00a0as 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."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "c85c6fadbef0",
                                            "version_value": "8f317cd88805"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "3869eecf0504",
                                            "version_value": "e0bcd6b57793"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "4ef0c5c6b5ba",
                                            "version_value": "589a954daab5"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "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"
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                                                "defaultStatus": "affected"
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    "references": {
        "reference_data": [
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                "url": "https://git.kernel.org/stable/c/8f317cd888059c59e2fa924bf4b0957cfa53f78e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/8f317cd888059c59e2fa924bf4b0957cfa53f78e"
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                "url": "https://git.kernel.org/stable/c/e0bcd6b5779352aed88f2e538a82a39f1a7715bb",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/e0bcd6b5779352aed88f2e538a82a39f1a7715bb"
            },
            {
                "url": "https://git.kernel.org/stable/c/589a954daab5e18399860b6c8ffaeaf79844eb20",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/589a954daab5e18399860b6c8ffaeaf79844eb20"
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                "url": "https://git.kernel.org/stable/c/13765de8148f71fa795e0a6607de37c49ea5915a",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/13765de8148f71fa795e0a6607de37c49ea5915a"
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