Ubuntu: (Multiple Advisories) (CVE-2024-40953): Linux kernel vulnerabilities

Ubuntu: (Multiple Advisories) (CVE-2024-40953): Linux kernel vulnerabilities

Severity

4

CVSS

(AV:L/AC:M/Au:N/C:P/I:P/A:P)

Published

07/12/2024

Created

09/13/2024

Added

09/12/2024

Modified

09/25/2024

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin() Use {READ,WRITE}_ONCE() to access kvm->last_boosted_vcpu to ensure the loads and stores are atomic.In the extremely unlikely scenario the compiler tears the stores, it's theoretically possible for KVM to attempt to get a vCPU using an out-of-bounds index, e.g. if the write is split into multiple 8-bit stores, and is paired with a 32-bit load on a VM with 257 vCPUs: CPU0CPU1 last_boosted_vcpu = 0xff; (last_boosted_vcpu = 0x100) last_boosted_vcpu[15:8] = 0x01; i = (last_boosted_vcpu = 0x1ff) last_boosted_vcpu[7:0] = 0x00; vcpu = kvm->vcpu_array[0x1ff]; As detected by KCSAN: BUG: KCSAN: data-race in kvm_vcpu_on_spin [kvm] / kvm_vcpu_on_spin [kvm] write to 0xffffc90025a92344 of 4 bytes by task 4340 on cpu 16: kvm_vcpu_on_spin (arch/x86/kvm/../../../virt/kvm/kvm_main.c:4112) kvm handle_pause (arch/x86/kvm/vmx/vmx.c:5929) kvm_intel vmx_handle_exit (arch/x86/kvm/vmx/vmx.c:? arch/x86/kvm/vmx/vmx.c:6606) kvm_intel vcpu_run (arch/x86/kvm/x86.c:11107 arch/x86/kvm/x86.c:11211) kvm kvm_arch_vcpu_ioctl_run (arch/x86/kvm/x86.c:?) kvm kvm_vcpu_ioctl (arch/x86/kvm/../../../virt/kvm/kvm_main.c:?) kvm __se_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:904 fs/ioctl.c:890) __x64_sys_ioctl (fs/ioctl.c:890) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/common.c:?) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) read to 0xffffc90025a92344 of 4 bytes by task 4342 on cpu 4: kvm_vcpu_on_spin (arch/x86/kvm/../../../virt/kvm/kvm_main.c:4069) kvm handle_pause (arch/x86/kvm/vmx/vmx.c:5929) kvm_intel vmx_handle_exit (arch/x86/kvm/vmx/vmx.c:? arch/x86/kvm/vmx/vmx.c:6606) kvm_intel vcpu_run (arch/x86/kvm/x86.c:11107 arch/x86/kvm/x86.c:11211) kvm kvm_arch_vcpu_ioctl_run (arch/x86/kvm/x86.c:?) kvm kvm_vcpu_ioctl (arch/x86/kvm/../../../virt/kvm/kvm_main.c:?) kvm __se_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:904 fs/ioctl.c:890) __x64_sys_ioctl (fs/ioctl.c:890) x64_sys_call (arch/x86/entry/syscall_64.c:33) do_syscall_64 (arch/x86/entry/common.c:?) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) value changed: 0x00000012 -> 0x00000000

Solution(s)

• ubuntu-upgrade-linux-image-6-8-0-1010-gke
• ubuntu-upgrade-linux-image-6-8-0-1011-raspi
• ubuntu-upgrade-linux-image-6-8-0-1012-ibm
• ubuntu-upgrade-linux-image-6-8-0-1012-oem
• ubuntu-upgrade-linux-image-6-8-0-1012-oracle
• ubuntu-upgrade-linux-image-6-8-0-1012-oracle-64k
• ubuntu-upgrade-linux-image-6-8-0-1013-nvidia
• ubuntu-upgrade-linux-image-6-8-0-1013-nvidia-64k
• ubuntu-upgrade-linux-image-6-8-0-1013-nvidia-lowlatency
• ubuntu-upgrade-linux-image-6-8-0-1013-nvidia-lowlatency-64k
• ubuntu-upgrade-linux-image-6-8-0-1014-azure
• ubuntu-upgrade-linux-image-6-8-0-1014-azure-fde
• ubuntu-upgrade-linux-image-6-8-0-1014-gcp
• ubuntu-upgrade-linux-image-6-8-0-1015-aws
• ubuntu-upgrade-linux-image-6-8-0-44-generic
• ubuntu-upgrade-linux-image-6-8-0-44-generic-64k
• ubuntu-upgrade-linux-image-6-8-0-44-lowlatency
• ubuntu-upgrade-linux-image-6-8-0-44-lowlatency-64k
• ubuntu-upgrade-linux-image-6-8-0-45-generic
• ubuntu-upgrade-linux-image-6-8-0-45-generic-64k
• ubuntu-upgrade-linux-image-aws
• ubuntu-upgrade-linux-image-azure
• ubuntu-upgrade-linux-image-azure-fde
• ubuntu-upgrade-linux-image-gcp
• ubuntu-upgrade-linux-image-generic
• ubuntu-upgrade-linux-image-generic-64k
• ubuntu-upgrade-linux-image-generic-64k-hwe-22-04
• ubuntu-upgrade-linux-image-generic-64k-hwe-24-04
• ubuntu-upgrade-linux-image-generic-hwe-22-04
• ubuntu-upgrade-linux-image-generic-hwe-24-04
• ubuntu-upgrade-linux-image-generic-lpae
• ubuntu-upgrade-linux-image-gke
• ubuntu-upgrade-linux-image-ibm
• ubuntu-upgrade-linux-image-ibm-classic
• ubuntu-upgrade-linux-image-ibm-lts-24-04
• ubuntu-upgrade-linux-image-kvm
• ubuntu-upgrade-linux-image-lowlatency
• ubuntu-upgrade-linux-image-lowlatency-64k
• ubuntu-upgrade-linux-image-lowlatency-64k-hwe-22-04
• ubuntu-upgrade-linux-image-lowlatency-hwe-22-04
• ubuntu-upgrade-linux-image-nvidia
• ubuntu-upgrade-linux-image-nvidia-6-8
• ubuntu-upgrade-linux-image-nvidia-64k
• ubuntu-upgrade-linux-image-nvidia-64k-6-8
• ubuntu-upgrade-linux-image-nvidia-lowlatency
• ubuntu-upgrade-linux-image-nvidia-lowlatency-64k
• ubuntu-upgrade-linux-image-oem-22-04
• ubuntu-upgrade-linux-image-oem-22-04a
• ubuntu-upgrade-linux-image-oem-22-04b
• ubuntu-upgrade-linux-image-oem-22-04c
• ubuntu-upgrade-linux-image-oem-22-04d
• ubuntu-upgrade-linux-image-oracle
• ubuntu-upgrade-linux-image-oracle-64k
• ubuntu-upgrade-linux-image-raspi
• ubuntu-upgrade-linux-image-virtual
• ubuntu-upgrade-linux-image-virtual-hwe-22-04
• ubuntu-upgrade-linux-image-virtual-hwe-24-04

References

• https://attackerkb.com/topics/cve-2024-40953
• CVE - 2024-40953
• USN-6999-1
• USN-6999-2
• USN-7004-1
• USN-7005-1
• USN-7005-2
• USN-7008-1
• USN-7029-1

View more