Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't zero the entire extent if EXT4_EXT_DATA_PARTIAL_VALID1
When allocating initialized blocks from a large unwritten extent, or
when splitting an unwritten extent during end I/O and converting it to
initialized, there is currently a potential issue of stale data if the
extent needs to be split in the middle.
0 A B N
[UUUUUUUUUUUU] U: unwritten extent
[--DDDDDDDD--] D: valid data
|<- ->| ----> this range needs to be initialized
ext4_split_extent() first try to split this extent at B with
EXT4_EXT_DATA_ENTIRE_VALID1 and EXT4_EXT_MAY_ZEROOUT flag set, but
ext4_split_extent_at() failed to split this extent due to temporary lack
of space. It zeroout B to N and mark the entire extent from 0 to N
as written.
0 A B N
[WWWWWWWWWWWW] W: written extent
[SSDDDDDDDDZZ] Z: zeroed, S: stale data
ext4_split_extent() then try to split this extent at A with
EXT4_EXT_DATA_VALID2 flag set. This time, it split successfully and left
a stale written extent from 0 to A.
0 A B N
[WW|WWWWWWWWWW]
[SS|DDDDDDDDZZ]
Fix this by pass EXT4_EXT_DATA_PARTIAL_VALID1 to ext4_split_extent_at()
when splitting at B, don't convert the entire extent to written and left
it as unwritten after zeroing out B to N. The remaining work is just
like the standard two-part split. ext4_split_extent() will pass the
EXT4_EXT_DATA_VALID2 flag when it calls ext4_split_extent_at() for the
second time, allowing it to properly handle the split. If the split is
successful, it will keep extent from 0 to A as unwritten.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 3.2.33 – < 3.3, 3.4.16 – < 3.5, 3.6.4 – < 3.7, 3.7 | 3.3 |
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 | 6.18.14-1 | — |
| Debian 13 | linux | 6.12.85-1 | — |
| Debian 12 | linux | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1028.33 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-136.136 | USN-8567-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1061.64 | USN-8595-2 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1063.71 | USN-8606-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1062.69 | USN-8607-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1064.72 | USN-8567-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1059.67 | USN-8567-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1046.50 | USN-8567-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1061.62 | USN-8574-3 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-136.136.2 | USN-8574-2 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1059.62 | USN-8596-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1059.62.1 | USN-8596-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1030.31 | USN-8574-3 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1058.61 | USN-8574-2 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1061.65 | USN-8665-1 |
| Ubuntu 24.04 LTS | linux-riscv +27 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-vmware | 6.8.0-1008.8 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1033.34 | USN-8574-3 |
| Ubuntu 22.04 LTS | linux +49 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1061.64~22.04.1 | USN-8595-3 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1063.71~22.04.1 | USN-8606-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1062.69~22.04.1 | USN-8609-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1064.72~22.04.1 | USN-8567-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-136.136~22.04.1 | USN-8619-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1061.62~22.04.1 | USN-8574-3 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-136.136.2~22.04.1 | USN-8574-2 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1059.62~22.04.1 | USN-8596-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1058.61~22.04.1 | USN-8595-1 |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-136.136~22.04.3 | — |
Show 18 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2050.52 | USN-8665-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1056.57 | USN-8567-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1056.57~22.04.2 | USN-8567-1 |
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1061.64+fips1 | USN-8595-3 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1063.71+fips2 | USN-8608-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-136.136+fips2 | USN-8574-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1064.72+fips1 | USN-8574-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux +21 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux +12 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | linux +7 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | linux +3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +4 | 6.4.0-150700.53.73.2 | SUSE-SU-2026:3166-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.73.2.150700.17.41.4 | SUSE-SU-2026:3166-1 |
| SLES 15 SP7 | kernel-docs +2 | 6.4.0-150700.53.73.1 | SUSE-SU-2026:3166-1 |
| SLES 12 SP5 | kernel-syms +2 | 4.12.14-122.323.1 | SUSE-SU-2026:3594-1 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.36.1 | SUSE-SU-2026:22835-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22835-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.36.1 | SUSE-SU-2026:22835-1, SUSE-SU-2026:22812-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22835-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22769-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.36.1 | SUSE-SU-2026:22769-1, SUSE-SU-2026:22742-1 |
| SLE Micro 6.1 | kernel-rt +2 | 6.4.0-50.1 | SUSE-SU-2026:22904-1, SUSE-SU-2026:22903-1 |
| SLE Micro 6.1 | kernel-source +1 | 6.4.0-50.2 | SUSE-SU-2026:22904-1, SUSE-SU-2026:22903-1 |
| SLE Micro 6.0 | kernel-rt +2 | 6.4.0-50.1 | SUSE-SU-2026:22810-1, SUSE-SU-2026:22809-1 |
| SLE Micro 6.0 | kernel-source +1 | 6.4.0-50.2 | SUSE-SU-2026:22810-1, SUSE-SU-2026:22809-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.73.2 | SUSE-SU-2026:3166-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_18 | 1-150700.1.5.1 | SUSE-SU-2026:3130-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_19 | 1-150700.15.3.4 | SUSE-SU-2026:3166-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.323.1 | SUSE-SU-2026:3594-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_86 | 1-8.3.1 | SUSE-SU-2026:3594-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.67.1 | SUSE-SU-2026:3130-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | openSUSE-SU-2026:21388-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.36.1 | openSUSE-SU-2026:21388-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.77-99.140 +2 | 1:1.0-0.amzn2023 | ALAS2023-2026-1681, ALAS2023-2026-1543, ALAS2023-2026-1514 |
| Amazon Linux 2023 | perf +14 | 1:6.1.168-202.320.amzn2023 | ALAS2023-2026-1681 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.77-99.140.amzn2023 | ALAS2023-2026-1543 |
| Amazon Linux 2023 | perf6.18 +14 | 1:6.18.15-14.217.amzn2023 | ALAS2023-2026-1514 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.139.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-204.92.4.2.el10uek | ELSA-2026-50372 |
Advisories 31
- WID-SEC-2026-1700 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8574-3 linux-ibm, linux-ibm-6.8, linux-nvidia-tegra, linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-3 linux-aws-6.8, linux-aws-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8574-2 linux-fips, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8596-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8665-1 linux-raspi, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8608-1 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8574-1 linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-2 linux-aws vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8595-1 linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8567-1 linux, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8606-1 linux-azure, linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8607-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8619-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8609-1 linux-azure-fde-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- ALAS2023-2026-1681 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 29, 2026
- SUSE-SU-2026:3594-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Aug 13, 2026
- SUSE-SU-2026:22903-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22904-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22835-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22809-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22810-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22812-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:21388-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 24, 2026
- SUSE-SU-2026:22769-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 23, 2026
- SUSE-SU-2026:22742-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 23, 2026
- SUSE-SU-2026:3166-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 22, 2026
- SUSE-SU-2026:3130-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 21, 2026
- ELSA-2026-50372 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 2, 2026
- ALAS2023-2026-1514 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
- ALAS2023-2026-1543 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
References
- https://git.kernel.org/stable/c/58ddae5d77b1db3a27b891c75a8fa120239ac092
- https://git.kernel.org/stable/c/d17857b4fb9ba5745b59be0ef38fd532991fccbf
- https://git.kernel.org/stable/c/d67c8ecf3d8fda9b8ef80e6f665d84b6d6ac9d88
- https://git.kernel.org/stable/c/7015fcf473796e1d2d876f241bd9e0c36f3d4eef
- https://git.kernel.org/stable/c/1bf6974822d1dba86cf11b5f05498581cf3488a2