{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-47592",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-24T15:11:00.733Z",
        "datePublished": "2024-06-19T14:53:55.574Z",
        "dateUpdated": "2024-08-04T05:47:39.480Z"
    },
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        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-06-19T14:53:55.574Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: stmmac: fix tc flower deletion for VLAN priority Rx steering\n\nTo replicate the issue:-\n\n1) Add 1 flower filter for VLAN Priority based frame steering:-\n$ IFDEVNAME=eth0\n$ tc qdisc add dev $IFDEVNAME ingress\n$ tc qdisc add dev $IFDEVNAME root mqprio num_tc 8 \\\n   map 0 1 2 3 4 5 6 7 0 0 0 0 0 0 0 0 \\\n   queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0\n$ tc filter add dev $IFDEVNAME parent ffff: protocol 802.1Q \\\n   flower vlan_prio 0 hw_tc 0\n\n2) Get the 'pref' id\n$ tc filter show dev $IFDEVNAME ingress\n\n3) Delete a specific tc flower record (say pref 49151)\n$ tc filter del dev $IFDEVNAME parent ffff: pref 49151\n\nFrom dmesg, we will observe kernel NULL pointer ooops\n\n[  197.170464] BUG: kernel NULL pointer dereference, address: 0000000000000000\n[  197.171367] #PF: supervisor read access in kernel mode\n[  197.171367] #PF: error_code(0x0000) - not-present page\n[  197.171367] PGD 0 P4D 0\n[  197.171367] Oops: 0000 [#1] PREEMPT SMP NOPTI\n\n<snip>\n\n[  197.171367] RIP: 0010:tc_setup_cls+0x20b/0x4a0 [stmmac]\n\n<snip>\n\n[  197.171367] Call Trace:\n[  197.171367]  <TASK>\n[  197.171367]  ? __stmmac_disable_all_queues+0xa8/0xe0 [stmmac]\n[  197.171367]  stmmac_setup_tc_block_cb+0x70/0x110 [stmmac]\n[  197.171367]  tc_setup_cb_destroy+0xb3/0x180\n[  197.171367]  fl_hw_destroy_filter+0x94/0xc0 [cls_flower]\n\nThe above issue is due to previous incorrect implementation of\ntc_del_vlan_flow(), shown below, that uses flow_cls_offload_flow_rule()\nto get struct flow_rule *rule which is no longer valid for tc filter\ndelete operation.\n\n  struct flow_rule *rule = flow_cls_offload_flow_rule(cls);\n  struct flow_dissector *dissector = rule->match.dissector;\n\nSo, to ensure tc_del_vlan_flow() deletes the right VLAN cls record for\nearlier configured RX queue (configured by hw_tc) in tc_add_vlan_flow(),\nthis patch introduces stmmac_rfs_entry as driver-side flow_cls_offload\nrecord for 'RX frame steering' tc flower, currently used for VLAN\npriority. The implementation has taken consideration for future extension\nto include other type RX frame steering such as EtherType based.\n\nv2:\n - Clean up overly extensive backtrace and rewrite git message to better\n   explain the kernel NULL pointer issue."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ethernet/stmicro/stmmac/stmmac.h",
                        "drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c"
                    ],
                    "versions": [
                        {
                            "version": "0e039f5cf86c",
                            "lessThan": "97cb5c82aa1d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "0e039f5cf86c",
                            "lessThan": "aeb7c75cb774",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ethernet/stmicro/stmmac/stmmac.h",
                        "drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c"
                    ],
                    "versions": [
                        {
                            "version": "5.13",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.13",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.15.11",
                            "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/97cb5c82aa1dd85a39b1bd021c8b5f18af623779"
                },
                {
                    "url": "https://git.kernel.org/stable/c/aeb7c75cb77478fdbf821628e9c95c4baa9adc63"
                }
            ],
            "title": "net: stmmac: fix tc flower deletion for VLAN priority Rx steering",
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                "engine": "bippy-a5840b7849dd"
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                            "content": {
                                "timestamp": "2024-06-20T15:19:38.436561Z",
                                "id": "CVE-2021-47592",
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                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/97cb5c82aa1dd85a39b1bd021c8b5f18af623779",
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