{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "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()."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/usb/dwc3/gadget.c"
               ],
               "versions": [
                  {
                     "version": "e81a7018d93a",
                     "lessThan": "1ea775021282",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e81a7018d93a",
                     "lessThan": "bc0cdd724932",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e81a7018d93a",
                     "lessThan": "b4b8e9601d7e",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e81a7018d93a",
                     "lessThan": "bb9c74a5bd14",
                     "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/usb/dwc3/gadget.c"
               ],
               "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"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/1ea775021282d90e1d08d696b7ab54aa75d688e5"
            },
            {
               "url": "https://git.kernel.org/stable/c/bc0cdd72493236fb72b390ad38ce581e353c143c"
            },
            {
               "url": "https://git.kernel.org/stable/c/b4b8e9601d7ee8806d2687f081a42485d27674a1"
            },
            {
               "url": "https://git.kernel.org/stable/c/bb9c74a5bd1462499fe5ccb1e3c5ac40dcfa9139"
            }
         ],
         "title": "usb: dwc3: gadget: Free gadget structure only after freeing endpoints",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-46986",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
