{
  "threat_severity" : "Low",
  "public_date" : "2024-04-02T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: x86/lib: Revert to _ASM_EXTABLE_UA() for {get,put}_user() fixups",
    "id" : "2272818",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2272818"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.4",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-99",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nx86/lib: Revert to _ASM_EXTABLE_UA() for {get,put}_user() fixups\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.\nmce: [Hardware Error]: CPU 296: Machine Check Exception: f Bank 1: bd80000000100134\nmce: [Hardware Error]: RIP 10:<ffffffff821b9776> {__get_user_nocheck_4+0x6/0x20}\nmce: [Hardware Error]: TSC 411a93533ed ADDR 346a8730040 MISC 86\nmce: [Hardware Error]: PROCESSOR 0:a06d0 TIME 1706000767 SOCKET 1 APIC 211 microcode 80001490\nmce: [Hardware Error]: Run the above through 'mcelog --ascii'\nmce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel\nKernel panic - not syncing: Fatal local machine check\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.\nex_handler_uaccess() would warn if users gave a non-canonical addresses\n(with bit 63 clear) to {get, put}_user(), which was unexpected.\nTherefore, commit\nb19b74bc99b1 (\"x86/mm: Rework address range check in get_user() and put_user()\")\nreplaced _ASM_EXTABLE_UA() with _ASM_EXTABLE() for {get, put}_user()\nfixups. However, the new fixup type EX_TYPE_DEFAULT results in a panic.\nCommit\n6014bc27561f (\"x86-64: make access_ok() independent of LAM\")\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.\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[ bp: Massage commit message. ]" ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-11-12T00:00:00Z",
    "advisory" : "RHSA-2024:9315",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-503.11.1.el9_5"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-11-12T00:00:00Z",
    "advisory" : "RHSA-2024:9315",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-503.11.1.el9_5"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2024-26674\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-26674\nhttps://lore.kernel.org/linux-cve-announce/2024040252-CVE-2024-26674-4ff9@gregkh/T" ],
  "name" : "CVE-2024-26674",
  "csaw" : false
}