{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/lib: Revert to _ASM_EXTABLE_UA() for {get,put}_user() fixups\n\nDuring memory error injection test on kernels >= v6.4, the kernel panics\nlike below. However, this issue couldn't be reproduced on kernels <= v6.3.\n\n  mce: [Hardware Error]: CPU 296: Machine Check Exception: f Bank 1: bd80000000100134\n  mce: [Hardware Error]: RIP 10:<ffffffff821b9776> {__get_user_nocheck_4+0x6/0x20}\n  mce: [Hardware Error]: TSC 411a93533ed ADDR 346a8730040 MISC 86\n  mce: [Hardware Error]: PROCESSOR 0:a06d0 TIME 1706000767 SOCKET 1 APIC 211 microcode 80001490\n  mce: [Hardware Error]: Run the above through 'mcelog --ascii'\n  mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel\n  Kernel panic - not syncing: Fatal local machine check\n\nThe MCA code can recover from an in-kernel #MC if the fixup type is\nEX_TYPE_UACCESS, explicitly indicating that the kernel is attempting to\naccess userspace memory. However, if the fixup type is EX_TYPE_DEFAULT\nthe only thing that is raised for an in-kernel #MC is a panic.\n\nex_handler_uaccess() would warn if users gave a non-canonical addresses\n(with bit 63 clear) to {get, put}_user(), which was unexpected.\n\nTherefore, commit\n\n  b19b74bc99b1 (\"x86/mm: Rework address range check in get_user() and put_user()\")\n\nreplaced _ASM_EXTABLE_UA() with _ASM_EXTABLE() for {get, put}_user()\nfixups. However, the new fixup type EX_TYPE_DEFAULT results in a panic.\n\nCommit\n\n  6014bc27561f (\"x86-64: make access_ok() independent of LAM\")\n\nadded the check gp_fault_address_ok() right before the WARN_ONCE() in\nex_handler_uaccess() to not warn about non-canonical user addresses due\nto LAM.\n\nWith that in place, revert back to _ASM_EXTABLE_UA() for {get,put}_user()\nexception fixups in order to be able to handle in-kernel MCEs correctly\nagain.\n\n  [ bp: Massage commit message. ]"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/x86/lib/getuser.S",
                  "arch/x86/lib/putuser.S"
               ],
               "versions": [
                  {
                     "version": "b19b74bc99b1",
                     "lessThan": "2aed1b6c33af",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b19b74bc99b1",
                     "lessThan": "2da241c5ed78",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b19b74bc99b1",
                     "lessThan": "8eed4e00a370",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/x86/lib/getuser.S",
                  "arch/x86/lib/putuser.S"
               ],
               "versions": [
                  {
                     "version": "6.4",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "6.4",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.6.17",
                     "lessThanOrEqual": "6.6.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.7.5",
                     "lessThanOrEqual": "6.7.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.8",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/2aed1b6c33afd8599d01c6532bbecb829480a674"
            },
            {
               "url": "https://git.kernel.org/stable/c/2da241c5ed78d0978228a1150735539fe1a60eca"
            },
            {
               "url": "https://git.kernel.org/stable/c/8eed4e00a370b37b4e5985ed983dccedd555ea9d"
            }
         ],
         "title": "x86/lib: Revert to _ASM_EXTABLE_UA() for {get,put}_user() fixups",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-26674",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}