{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndevice-dax: correct pgoff align in dax_set_mapping()\n\npgoff should be aligned using ALIGN_DOWN() instead of ALIGN().  Otherwise,\nvmf->address not aligned to fault_size will be aligned to the next\nalignment, that can result in memory failure getting the wrong address.\n\nIt's a subtle situation that only can be observed in\npage_mapped_in_vma() after the page is page fault handled by\ndev_dax_huge_fault.  Generally, there is little chance to perform\npage_mapped_in_vma in dev-dax's page unless in specific error injection\nto the dax device to trigger an MCE - memory-failure.  In that case,\npage_mapped_in_vma() will be triggered to determine which task is\naccessing the failure address and kill that task in the end.\n\n\nWe used self-developed dax device (which is 2M aligned mapping) , to\nperform error injection to random address.  It turned out that error\ninjected to non-2M-aligned address was causing endless MCE until panic.\nBecause page_mapped_in_vma() kept resulting wrong address and the task\naccessing the failure address was never killed properly:\n\n\n[ 3783.719419] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3784.049006] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3784.049190] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3784.448042] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3784.448186] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3784.792026] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3784.792179] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3785.162502] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3785.162633] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3785.461116] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3785.461247] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3785.764730] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3785.764859] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3786.042128] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3786.042259] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3786.464293] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3786.464423] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3786.818090] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3786.818217] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n[ 3787.085297] mce: Uncorrected hardware memory error in user-access at \n200c9742380\n[ 3787.085424] Memory failure: 0x200c9742: recovery action for dax page: \nRecovered\n\nIt took us several weeks to pinpoint this problem,  but we eventually\nused bpftrace to trace the page fault and mce address and successfully\nidentified the issue.\n\n\nJoao added:\n\n; Likely we never reproduce in production because we always pin\n: device-dax regions in the region align they provide (Qemu does\n: similarly with prealloc in hugetlb/file backed memory).  I think this\n: bug requires that we touch *unpinned* device-dax regions unaligned to\n: the device-dax selected alignment (page size i.e.  4K/2M/1G)"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/dax/device.c"
               ],
               "versions": [
                  {
                     "version": "b9b5777f09be",
                     "lessThan": "9c4198dfdca8",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b9b5777f09be",
                     "lessThan": "b822007e8db3",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b9b5777f09be",
                     "lessThan": "e877427d2181",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b9b5777f09be",
                     "lessThan": "7fcbd9785d4c",
                     "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/dax/device.c"
               ],
               "versions": [
                  {
                     "version": "5.17",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.17",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.1.113",
                     "lessThanOrEqual": "6.1.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.6.57",
                     "lessThanOrEqual": "6.6.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.11.4",
                     "lessThanOrEqual": "6.11.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.12-rc3",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/9c4198dfdca818c5ce19c764d90eabd156bbc6da"
            },
            {
               "url": "https://git.kernel.org/stable/c/b822007e8db341d6f175c645ed79866db501ad86"
            },
            {
               "url": "https://git.kernel.org/stable/c/e877427d218159ac29c9326100920d24330c9ee6"
            },
            {
               "url": "https://git.kernel.org/stable/c/7fcbd9785d4c17ea533c42f20a9083a83f301fa6"
            }
         ],
         "title": "device-dax: correct pgoff align in dax_set_mapping()",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-50022",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}