Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't cache extent during splitting extent
Caching extents during the splitting process is risky, as it may result
in stale extents remaining in the status tree. Moreover, in most cases,
the corresponding extent block entries are likely already cached before
the split happens, making caching here not particularly useful.
Assume we have an unwritten extent, and then DIO writes the first half.
[UUUUUUUUUUUUUUUU] on-disk extent U: unwritten extent
[UUUUUUUUUUUUUUUU] extent status tree
|<- ->| ----> dio write this range
First, when ext4_split_extent_at() splits this extent, it truncates the
existing extent and then inserts a new one. During this process, this
extent status entry may be shrunk, and calls to ext4_find_extent() and
ext4_cache_extents() may occur, which could potentially insert the
truncated range as a hole into the extent status tree. After the split
is completed, this hole is not replaced with the correct status.
[UUUUUUU|UUUUUUUU] on-disk extent U: unwritten extent
[UUUUUUU|HHHHHHHH] extent status tree H: hole
Then, the outer calling functions will not correct this remaining hole
extent either. Finally, if we perform a delayed buffer write on this
latter part, it will re-insert the delayed extent and cause an error in
space accounting.
In adition, if the unwritten extent cache is not shrunk during the
splitting, ext4_cache_extents() also conflicts with existing extents
when caching extents. In the future, we will add checks when caching
extents, which will trigger a warning. Therefore, Do not cache extents
that are being split.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 3.12 | 5.10.252 |
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 | 6.1.170-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1026.30 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1096.98 | — |
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-134.134 | USN-8492-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1060.63 | USN-8492-1 |
| 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-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1063.69 | USN-8492-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1058.64 | USN-8492-2 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1045.48 | USN-8492-2 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1060.61 | USN-8492-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-134.134.1 | USN-8497-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1058.61 | USN-8492-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1058.61.1 | USN-8492-2 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1029.30 | USN-8498-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1057.58 | USN-8492-1 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1060.64 | USN-8492-4 |
| Ubuntu 24.04 LTS | linux-riscv +26 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1032.33 | USN-8499-1 |
| Ubuntu 22.04 LTS | linux | 5.15.0-186.196 | USN-8575-1 |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1112.119 | USN-8575-2 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1060.63~22.04.1 | USN-8492-2 |
| Ubuntu 22.04 LTS | linux-azure +1 | 5.15.0-1117.126 | USN-8610-1, USN-8575-3 |
| 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 | 5.15.0-1112.122 | USN-8575-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1063.69~22.04.1 | USN-8492-2 |
| Ubuntu 22.04 LTS | linux-gke | 5.15.0-1108.114 | USN-8575-1 |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1095.103 | USN-8575-1 |
| 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 | 5.15.0-1106.110 | USN-8575-2 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1060.61~22.04.1 | USN-8492-2 |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1107.113 | USN-8620-4 |
| Ubuntu 22.04 LTS | linux-kvm | 5.15.0-1104.109 | USN-8575-1 |
| Ubuntu 22.04 LTS | linux-lowlatency | 5.15.0-184.194 | USN-8575-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-134.134.1~22.04.1 | USN-8497-1 |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1107.108 | USN-8575-2 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1058.61~22.04.1 | USN-8492-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1064.66 | USN-8576-2 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1053.53 | USN-8576-2 |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1109.115 | USN-8575-3 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1057.58~22.04.1 | USN-8492-2 |
| Ubuntu 22.04 LTS | linux-raspi | 5.15.0-1106.109 | USN-8668-2 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-134.134~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-xilinx-zynqmp | 5.15.0-1075.79 | USN-8575-1 |
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 | 6.8.0-2049.50 | USN-8492-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1055.56 | USN-8492-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1104.106 | USN-8620-3 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1111.120 | USN-8575-1 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1055.56~22.04.1 | USN-8492-1 |
| 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 | 6.8.0-1060.63+fips1 | USN-8492-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1062.69+fips1 | USN-8492-5 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-134.134+fips1 | USN-8492-5 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1063.69+fips1 | USN-8492-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-aws-fips | 5.15.0-1112.119+fips1 | USN-8575-2 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-azure-fips | 5.15.0-1117.126+fips1 | USN-8620-2 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips | 5.15.0-186.196+fips1 | USN-8575-2 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-gcp-fips | 5.15.0-1112.122+fips1 | USN-8575-1 |
| 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 +10 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux-aws-5.15 | 5.15.0-1112.119~20.04.1 | USN-8575-2 |
| Ubuntu Pro 20.04 LTS | linux-azure-5.15 | 5.15.0-1117.126~20.04.1 | USN-8620-1 |
| Ubuntu Pro 20.04 LTS | linux-azure-fde-5.15 | 5.15.0-1117.126~20.04.2 | USN-8620-1 |
| Ubuntu Pro 20.04 LTS | linux-gcp-5.15 | 5.15.0-1112.122~20.04.1 | USN-8668-1 |
| Ubuntu Pro 20.04 LTS | linux-hwe-5.15 | 5.15.0-186.196~20.04.1 | USN-8575-1 |
| Ubuntu Pro 20.04 LTS | linux-ibm-5.15 +1 | 5.15.0-1106.110~20.04.1 | USN-8597-1 |
| Ubuntu Pro 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1107.113~20.04.1 | USN-8620-3 |
| Ubuntu Pro 20.04 LTS | linux-lowlatency-hwe-5.15 | 5.15.0-184.194~20.04.1 | USN-8575-1 |
| Ubuntu Pro 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1064.66~20.04.1 | USN-8576-1 |
| Ubuntu Pro 20.04 LTS | linux-oracle-5.15 | 5.15.0-1109.115~20.04.1 | USN-8620-1 |
| 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 +6 | 6.4.0-150700.53.66.1 | SUSE-SU-2026:2800-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.66.1.150700.17.39.1 | SUSE-SU-2026:2800-1 |
| SLES 15 SP7 | kernel-docs | 6.4.0-150700.53.66.2 | SUSE-SU-2026:2800-1 |
| SLES 12 SP5 | kernel-syms +2 | 4.12.14-122.320.1 | SUSE-SU-2026:2914-1 |
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 +4 | 6.4.0-49.1 | SUSE-SU-2026:22666-1, SUSE-SU-2026:22665-1 |
| SLE Micro 6.0 | kernel-rt +4 | 6.4.0-49.1 | SUSE-SU-2026:22522-1, SUSE-SU-2026:22521-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.66.1 | SUSE-SU-2026:2800-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_17 | 1-150700.1.3.1 | SUSE-SU-2026:2799-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_18 | 1-150700.15.3.1 | SUSE-SU-2026:2800-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.320.1 | SUSE-SU-2026:2914-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_85 | 1-8.3.1 | SUSE-SU-2026:2914-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.62.1 | SUSE-SU-2026:2799-1 |
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 | ALAS2023-2026-1544, ALAS2023-2026-1543, ALAS2023-2026-1514 |
| Amazon Linux 2023 | perf +14 | 1:6.1.166-197.305.amzn2023 | ALAS2023-2026-1544 |
| 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 42
- WID-SEC-2026-1700 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8575-1 linux, linux-gcp, linux-gcp-fips, linux-gke, linux-gkeop, linux-hwe-5.15, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-realtime, linux-xilinx-zynqmp vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8575-2 linux-aws, linux-aws-5.15, linux-aws-fips, linux-fips, linux-ibm, linux-nvidia vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8620-1 linux-azure-5.15, linux-azure-fde-5.15, linux-oracle-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8620-3 linux-intel-iot-realtime, linux-intel-iotg-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8668-2 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8610-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8575-3 linux-azure, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8668-1 linux-gcp-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8576-1 linux-nvidia-tegra-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8576-2 linux-nvidia-tegra, linux-nvidia-tegra-igx vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8620-4 linux-intel-iotg vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8620-2 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 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-8597-1 linux-ibm-5.15 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
- USN-8499-1 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8497-1 linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8492-1 linux, linux-aws, linux-aws-fips, linux-gcp, linux-gcp-fips, linux-ibm, linux-nvidia, linux-nvidia-6.8, linux-oracle, linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- USN-8492-2 linux-aws-6.8, linux-gcp-6.8, linux-gke, linux-gkeop, linux-ibm-6.8, linux-nvidia-lowlatency, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- USN-8498-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- USN-8492-3 linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- USN-8492-5 linux-azure-fips, linux-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- USN-8492-4 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 6, 2026
- SUSE-SU-2026:22835-1 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-2026:22665-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 21, 2026
- SUSE-SU-2026:22666-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 21, 2026
- SUSE-SU-2026:2914-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 14, 2026
- SUSE-SU-2026:22521-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:22522-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:2799-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:2800-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- ELSA-2026-50372 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 2, 2026
- ALAS2023-2026-1543 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
- ALAS2023-2026-1544 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
- ALAS2023-2026-1514 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
References
- https://git.kernel.org/stable/c/8302b5b4aacdbb378f7b1216bb2ee782b5142415
- https://git.kernel.org/stable/c/692103feca376ae4298c92aa8828015d20f1d87b
- https://git.kernel.org/stable/c/4c2d9dac4d328244f9365b0a1fa27ec802821820
- https://git.kernel.org/stable/c/93b2ebbbcb2e63cfc21a1946dfe91d3aa7952036
- https://git.kernel.org/stable/c/96007fd3c106aea773c1afae2d6f64cceb6da208
- https://git.kernel.org/stable/c/5b1f4290453314e11cd8e15c7baa8a9b76c19b23
- https://git.kernel.org/stable/c/9a2b95cdaf07785e2739199037bd9c0863ccc1be
- https://git.kernel.org/stable/c/8b4b19a2f96348d70bfa306ef7d4a13b0bcbea79