{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nisdn: cpai: check ctr->cnr to avoid array index out of bound\n\nThe cmtp_add_connection() would add a cmtp session to a controller\nand run a kernel thread to process cmtp.\n\n\t__module_get(THIS_MODULE);\n\tsession->task = kthread_run(cmtp_session, session, \"kcmtpd_ctr_%d\",\n\t\t\t\t\t\t\t\tsession->num);\n\nDuring this process, the kernel thread would call detach_capi_ctr()\nto detach a register controller. if the controller\nwas not attached yet, detach_capi_ctr() would\ntrigger an array-index-out-bounds bug.\n\n[   46.866069][ T6479] UBSAN: array-index-out-of-bounds in\ndrivers/isdn/capi/kcapi.c:483:21\n[   46.867196][ T6479] index -1 is out of range for type 'capi_ctr *[32]'\n[   46.867982][ T6479] CPU: 1 PID: 6479 Comm: kcmtpd_ctr_0 Not tainted\n5.15.0-rc2+ #8\n[   46.869002][ T6479] Hardware name: QEMU Standard PC (i440FX + PIIX,\n1996), BIOS 1.14.0-2 04/01/2014\n[   46.870107][ T6479] Call Trace:\n[   46.870473][ T6479]  dump_stack_lvl+0x57/0x7d\n[   46.870974][ T6479]  ubsan_epilogue+0x5/0x40\n[   46.871458][ T6479]  __ubsan_handle_out_of_bounds.cold+0x43/0x48\n[   46.872135][ T6479]  detach_capi_ctr+0x64/0xc0\n[   46.872639][ T6479]  cmtp_session+0x5c8/0x5d0\n[   46.873131][ T6479]  ? __init_waitqueue_head+0x60/0x60\n[   46.873712][ T6479]  ? cmtp_add_msgpart+0x120/0x120\n[   46.874256][ T6479]  kthread+0x147/0x170\n[   46.874709][ T6479]  ? set_kthread_struct+0x40/0x40\n[   46.875248][ T6479]  ret_from_fork+0x1f/0x30\n[   46.875773][ T6479]"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/isdn/capi/kcapi.c"
               ],
               "versions": [
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "e8b8de17e164",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "24219a977bfe",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "9b6b2db77bc3",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "7d91adc0ccb0",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "285e9210b1fa",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "7f221ccbee4e",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "cc20226e218a",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "1f3e2e97c003",
                     "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/isdn/capi/kcapi.c"
               ],
               "versions": [
                  {
                     "version": "4.4.290",
                     "lessThanOrEqual": "4.4.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "4.9.288",
                     "lessThanOrEqual": "4.9.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "4.14.253",
                     "lessThanOrEqual": "4.14.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "4.19.214",
                     "lessThanOrEqual": "4.19.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.4.156",
                     "lessThanOrEqual": "5.4.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.76",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.14.15",
                     "lessThanOrEqual": "5.14.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/e8b8de17e164c9f1b7777f1c6f99d05539000036"
            },
            {
               "url": "https://git.kernel.org/stable/c/24219a977bfe3d658687e45615c70998acdbac5a"
            },
            {
               "url": "https://git.kernel.org/stable/c/9b6b2db77bc3121fe435f1d4b56e34de443bec75"
            },
            {
               "url": "https://git.kernel.org/stable/c/7d91adc0ccb060ce564103315189466eb822cc6a"
            },
            {
               "url": "https://git.kernel.org/stable/c/285e9210b1fab96a11c0be3ed5cea9dd48b6ac54"
            },
            {
               "url": "https://git.kernel.org/stable/c/7f221ccbee4ec662e2292d490a43ce6c314c4594"
            },
            {
               "url": "https://git.kernel.org/stable/c/cc20226e218a2375d50dd9ac14fb4121b43375ff"
            },
            {
               "url": "https://git.kernel.org/stable/c/1f3e2e97c003f80c4b087092b225c8787ff91e4d"
            }
         ],
         "title": "isdn: cpai: check ctr->cnr to avoid array index out of bound",
         "x_generator": {
            "engine": "bippy-7d53e8ef8be4"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-4439",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}