Description
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Mark target gfn of emulated atomic instruction as dirty
When emulating an atomic access on behalf of the guest, mark the target
gfn dirty if the CMPXCHG by KVM is attempted and doesn't fault. This
fixes a bug where KVM effectively corrupts guest memory during live
migration by writing to guest memory without informing userspace that the
page is dirty.
Marking the page dirty got unintentionally dropped when KVM's emulated
CMPXCHG was converted to do a user access. Before that, KVM explicitly
mapped the guest page into kernel memory, and marked the page dirty during
the unmap phase.
Mark the page dirty even if the CMPXCHG fails, as the old data is written
back on failure, i.e. the page is still written. The value written is
guaranteed to be the same because the operation is atomic, but KVM's ABI
is that all writes are dirty logged regardless of the value written. And
more importantly, that's what KVM did before the buggy commit.
Huge kudos to the folks on the Cc list (and many others), who did all the
actual work of triaging and debugging.
base-commit: 6769ea8da8a93ed4630f1ce64df6aafcaabfce64
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.15.58 – < 5.15.154, 5.17.13 – < 5.18, 5.18.2 – < 5.19, 5.19 | 5.15.154 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.7.12-1 | — |
| Debian 13 | linux | 6.7.12-1 | — |
| Debian 12 | linux | 6.1.85-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1047.49 | — |
| Ubuntu 22.04 LTS | linux +1 | 5.15.0-116.126 | USN-6898-2, USN-6898-1 |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1065.71 | USN-6898-3 |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1068.77 | USN-6917-1 |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1068.77.1 | USN-6917-1 |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1064.72 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-gke | 5.15.0-1062.68 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1048.55 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-ibm +1 | 5.15.0-1058.61 | USN-6919-1, USN-6898-1 |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1060.66 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-kvm | 5.15.0-1062.67 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1060.61 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1026.26 | — |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1015.15 | — |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1063.69 | USN-6898-1 |
| Ubuntu 22.04 LTS | linux-riscv +31 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-xilinx-zynqmp | 5.15.0-1035.39 | USN-7019-1 |
| Ubuntu 20.04 LTS | linux-aws-5.15 | 5.15.0-1065.71~20.04.1 | USN-6898-4 |
| Ubuntu 20.04 LTS | linux-azure-5.15 | 5.15.0-1068.77~20.04.1 | USN-6917-1 |
| Ubuntu 20.04 LTS | linux-azure-fde-5.15 | 5.15.0-1068.77~20.04.1.1 | USN-6917-1 |
| Ubuntu 20.04 LTS | linux-gcp-5.15 | 5.15.0-1065.73~20.04.1 | USN-6927-1 |
| Ubuntu 20.04 LTS | linux-gke +26 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gkeop-5.15 | 5.15.0-1048.55~20.04.1 | USN-6898-1 |
| Ubuntu 20.04 LTS | linux-hwe-5.15 +1 | 5.15.0-116.126~20.04.1 | USN-6898-3, USN-6898-2 |
| Ubuntu 20.04 LTS | linux-ibm-5.15 | 5.15.0-1058.61~20.04.1 | USN-6898-2 |
| Ubuntu 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1060.66~20.04.1 | USN-6898-1 |
| Ubuntu 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1027.27~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-oracle-5.15 | 5.15.0-1063.69~20.04.1 | USN-6898-2 |
| Ubuntu 20.04 LTS | linux-riscv-5.15 | 5.15.0-1061.65~20.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp +13 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2002.2 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1058.60 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1066.74 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-aws-fips | 5.15.0-1065.71+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-azure-fips | 5.15.0-1068.77+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips | 5.15.0-115.125+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-gcp-fips | 5.15.0-1064.72+fips1 | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | kernel-64kb +3 | 6.4.0-150600.23.7.3 | SUSE-SU-2024:2203-1 |
| SLES 15 SP6 | kernel-azure +1 | 6.4.0-150600.8.5.4 | SUSE-SU-2024:2135-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.7.3.150600.12.2.7 | SUSE-SU-2024:2203-1 |
| SLES 15 SP6 | kernel-docs | 6.4.0-150600.23.7.4 | SUSE-SU-2024:2203-1 |
| SLES 15 SP6 | kernel-source | 6.4.0-150600.23.7.2 | SUSE-SU-2024:2203-1 |
| SLES 15 SP6 | kernel-syms | 6.4.0-150600.23.7.1 | SUSE-SU-2024:2203-1 |
| SLES 15 SP6 | kernel-syms-azure | 6.4.0-150600.8.5.1 | SUSE-SU-2024:2135-1 |
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.68.1 | SUSE-SU-2024:2190-1 |
| SLES 15 SP5 | kernel-azure +2 | 5.14.21-150500.33.57.1 | SUSE-SU-2024:2019-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.68.1.150500.6.31.1 | SUSE-SU-2024:2190-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.0 | kernel-default-base | 6.4.0-17.1.1.51 | SUSE-SU-2025:20008-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-9.1 | SUSE-SU-2025:20028-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-18.1 | SUSE-SU-2025:20008-1 |
| SLE Micro 5.5 | kernel-default | 5.14.21-150500.55.68.1 | SUSE-SU-2024:2190-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.68.1.150500.6.31.1 | SUSE-SU-2024:2190-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.58.1 | SUSE-SU-2024:2008-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.7.3 | SUSE-SU-2024:2203-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_1 | 1-150600.1.5.1 | SUSE-SU-2024:2973-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_1 | 1-150600.13.3.7 | SUSE-SU-2024:2203-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.68.1 | SUSE-SU-2024:2190-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_15 +1 | 1-150500.11.3.1 | SUSE-SU-2024:2190-1, SUSE-SU-2024:2008-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.5.1 | SUSE-SU-2024:2973-1 |
| SUSE Real Time Module 15 SP5 | kernel-rt +3 | 5.14.21-150500.13.58.1 | SUSE-SU-2024:2008-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +2 | 6.4.0-150600.23.7.1 | SUSE-SU-2024:2203-1 |
| openSUSE Leap 15.6 | kernel-64kb +5 | 6.4.0-150600.23.7.3 | SUSE-SU-2024:2203-1 |
| openSUSE Leap 15.6 | kernel-azure +1 | 6.4.0-150600.8.5.4 | SUSE-SU-2024:2135-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.7.3.150600.12.2.7 | SUSE-SU-2024:2203-1 |
| openSUSE Leap 15.6 | kernel-docs | 6.4.0-150600.23.7.4 | SUSE-SU-2024:2203-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.5.1 | SUSE-SU-2024:2973-1 |
| openSUSE Leap 15.6 | kernel-source | 6.4.0-150600.23.7.2 | SUSE-SU-2024:2203-1 |
| openSUSE Leap 15.6 | kernel-syms-azure | 6.4.0-150600.8.5.1 | SUSE-SU-2024:2135-1 |
| openSUSE Leap 15.5 | dtb-aarch64 +10 | 5.14.21-150500.55.68.1 | SUSE-SU-2024:2190-1 |
| openSUSE Leap 15.5 | kernel-azure +2 | 5.14.21-150500.33.57.1 | SUSE-SU-2024:2019-1 |
| openSUSE Leap 15.5 | kernel-default-base | 5.14.21-150500.55.68.1.150500.6.31.1 | SUSE-SU-2024:2190-1 |
| openSUSE Leap 15.5 | kernel-rt +3 | 5.14.21-150500.13.58.1 | SUSE-SU-2024:2008-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.1.84-99.169 | 1.0-0.amzn2023 | ALAS2023-2024-696 |
| Amazon Linux 2023 | perf +14 | 6.1.84-99.169.amzn2023 | ALAS2023-2024-696 |
Advisories 18
- WID-SEC-2024-1188 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 9, 2026
- USN-6919-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Oct 27, 2026
- USN-7019-1 linux-xilinx-zynqmp vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-6917-1 linux-azure, linux-azure-5.15, linux-azure-fde, linux-azure-fde-5.15 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-6927-1 linux-gcp-5.15 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-6898-1 linux, linux-gcp, linux-gke, linux-gkeop, linux-gkeop-5.15, linux-ibm, linux-intel-iotg, linux-intel-iotg-5.15, linux-kvm, linux-nvidia, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Oct 23, 2026
- USN-6898-2 linux-ibm-5.15, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-oracle-5.15 vulnerabilities Ubuntu Security Notices (USN) · Oct 23, 2026
- USN-6898-3 linux-aws, linux-hwe-5.15 vulnerabilities Ubuntu Security Notices (USN) · Oct 23, 2026
- USN-6898-4 linux-aws-5.15 vulnerabilities Ubuntu Security Notices (USN) · Oct 23, 2026
- SUSE-SU-2025:20008-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20028-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2024:2973-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2019-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2190-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2008-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2135-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ALAS2023-2024-696 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 2, 2025
- SUSE-SU-2024:2203-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
References
- https://git.kernel.org/stable/c/a9bd6bb6f02bf7132c1ab192ba62bbfa52df7d66
- https://git.kernel.org/stable/c/726374dde5d608b15b9756bd52b6fc283fda7a06
- https://git.kernel.org/stable/c/9d1b22e573a3789ed1f32033ee709106993ba551
- https://git.kernel.org/stable/c/225d587a073584946c05c9b7651d637bd45c0c71
- https://git.kernel.org/stable/c/910c57dfa4d113aae6571c2a8b9ae8c430975902