{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2021-46986",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: dwc3: gadget: Free gadget structure only after freeing endpoints\n\nAs part of commit e81a7018d93a (\"usb: dwc3: allocate gadget structure\ndynamically\") the dwc3_gadget_release() was added which will free\nthe dwc->gadget structure upon the device's removal when\nusb_del_gadget_udc() is called in dwc3_gadget_exit().\n\nHowever, simply freeing the gadget results a dangling pointer\nsituation: the endpoints created in dwc3_gadget_init_endpoints()\nhave their dep->endpoint.ep_list members chained off the list_head\nanchored at dwc->gadget->ep_list.  Thus when dwc->gadget is freed,\nthe first dwc3_ep in the list now has a dangling prev pointer and\nlikewise for the next pointer of the dwc3_ep at the tail of the list.\nThe dwc3_gadget_free_endpoints() that follows will result in a\nuse-after-free when it calls list_del().\n\nThis was caught by enabling KASAN and performing a driver unbind.\nThe recent commit 568262bf5492 (\"usb: dwc3: core: Add shutdown\ncallback for dwc3\") also exposes this as a panic during shutdown.\n\nThere are a few possibilities to fix this.  One could be to perform\na list_del() of the gadget->ep_list itself which removes it from\nthe rest of the dwc3_ep chain.\n\nAnother approach is what this patch does, by splitting up the\nusb_del_gadget_udc() call into its separate \"del\" and \"put\"\ncomponents.  This allows dwc3_gadget_free_endpoints() to be\ncalled before the gadget is finally freed with usb_put_gadget()."
            }
        ]
    },
    "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": "e81a7018d93a",
                                            "version_value": "1ea775021282"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.10",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "5.10",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.10.38",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.11.22",
                                                        "lessThanOrEqual": "5.11.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.12.5",
                                                        "lessThanOrEqual": "5.12.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.13",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/1ea775021282d90e1d08d696b7ab54aa75d688e5",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/1ea775021282d90e1d08d696b7ab54aa75d688e5"
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            {
                "url": "https://git.kernel.org/stable/c/bc0cdd72493236fb72b390ad38ce581e353c143c",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/bc0cdd72493236fb72b390ad38ce581e353c143c"
            },
            {
                "url": "https://git.kernel.org/stable/c/b4b8e9601d7ee8806d2687f081a42485d27674a1",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/b4b8e9601d7ee8806d2687f081a42485d27674a1"
            },
            {
                "url": "https://git.kernel.org/stable/c/bb9c74a5bd1462499fe5ccb1e3c5ac40dcfa9139",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/bb9c74a5bd1462499fe5ccb1e3c5ac40dcfa9139"
            }
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