Skip to content
OpenAdvisories
Unscored CVE-2026-45920 EUVD-2026-32386GHSA-r62x-r6m8-28mx

ext4: fix dirtyclusters double decrement on fs shutdown

Published May 27, 2026 · Updated Nov 6, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: linux Package: linux Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.15 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.4 Package: linux-aws-5.8 Package: linux-aws-6.14 Package: linux-aws-6.17 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-fips Package: linux-aws-hwe Package: linux-azure Package: linux-azure-4.15 Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.15 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.4 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.15 Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fips Package: linux-azure-nvidia Package: linux-azure-nvidia-6.14 Package: linux-bluefield Package: linux-fips Package: linux-gcp Package: linux-gcp-4.15 Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.15 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.4 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-fips Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.15 Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.15 Package: linux-hwe-5.19 Package: linux-hwe-5.4 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-edge Package: linux-ibm Package: linux-ibm-5.15 Package: linux-ibm-5.4 Package: linux-ibm-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-intel-iotg Package: linux-intel-iotg-5.15 Package: linux-iot Package: linux-kvm Package: linux-lowlatency Package: linux-lowlatency-hwe-5.15 Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.11 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-lowlatency-hwe-6.8 Package: linux-lts-xenial Package: linux-nvidia Package: linux-nvidia-6.11 Package: linux-nvidia-6.17 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-6.8 Package: linux-nvidia-lowlatency Package: linux-nvidia-tegra Package: linux-nvidia-tegra-5.15 Package: linux-nvidia-tegra-igx Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oem-6.11 Package: linux-oem-6.14 Package: linux-oem-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.15 Package: linux-oracle-5.3 Package: linux-oracle-5.4 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-raspi Package: linux-raspi-5.4 Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 Package: linux-realtime-6.8 Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.15 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-riscv-6.14 Package: linux-riscv-6.17 Package: linux-riscv-6.5 Package: linux-riscv-6.8 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Package: linux-xilinx Package: linux-xilinx-zynqmp Platform: Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

In the Linux kernel, the following vulnerability has been resolved:

ext4: fix dirtyclusters double decrement on fs shutdown

fstests test generic/388 occasionally reproduces a warning in
ext4_put_super() associated with the dirty clusters count:

WARNING: CPU: 7 PID: 76064 at fs/ext4/super.c:1324 ext4_put_super+0x48c/0x590 [ext4]

Tracing the failure shows that the warning fires due to an
s_dirtyclusters_counter value of -1. IOW, this appears to be a
spurious decrement as opposed to some sort of leak. Further tracing
of the dirty cluster count deltas and an LLM scan of the resulting
output identified the cause as a double decrement in the error path
between ext4_mb_mark_diskspace_used() and the caller
ext4_mb_new_blocks().

First, note that generic/388 is a shutdown vs. fsstress test and so
produces a random set of operations and shutdown injections. In the
problematic case, the shutdown triggers an error return from the
ext4_handle_dirty_metadata() call(s) made from
ext4_mb_mark_context(). The changed value is non-zero at this point,
so ext4_mb_mark_diskspace_used() does not exit after the error
bubbles up from ext4_mb_mark_context(). Instead, the former
decrements both cluster counters and returns the error up to
ext4_mb_new_blocks(). The latter falls into the !ar->len out path
which decrements the dirty clusters counter a second time, creating
the inconsistency.

To avoid this problem and simplify ownership of the cluster
reservation in this codepath, lift the counter reduction to a single
place in the caller. This makes it more clear that
ext4_mb_new_blocks() is responsible for acquiring cluster
reservation (via ext4_claim_free_clusters()) in the !delalloc case
as well as releasing it, regardless of whether it ends up consumed
or returned due to failure.

Affected products

VendorProductAffectedFixed
Linux Linux 2.6.29 5.10.253

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.

ReleasePackageFixed inAdvisory
Debian 14 linux 6.18.14-1 —
Debian 13 linux 6.12.85-1 —
Debian 12 linux 6.1.170-1 —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1028.33 —
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 6.8.0-136.136 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 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 6.8.0-1061.64~22.04.1 USN-8595-3
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 6.8.0-1064.72~22.04.1 USN-8567-1
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 6.8.0-1061.62~22.04.1 USN-8574-3
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 6.8.0-136.136.2~22.04.1 USN-8574-2
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1107.108 USN-8575-2
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1059.62~22.04.1 USN-8596-1
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 6.8.0-1058.61~22.04.1 USN-8595-1
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 6.8.0-136.136~22.04.3 —
Ubuntu 22.04 LTS linux-xilinx-zynqmp 5.15.0-1075.79 USN-8575-1
Show 18 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
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-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 6.8.1-1056.57~22.04.2 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-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 —
ReleasePackageFixed inAdvisory
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)
ReleasePackageFixed inAdvisory
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
ReleasePackageFixed inAdvisory
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

ReleasePackageFixed inAdvisory
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

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 9 kernel-uek +34 6.12.0-204.92.4.2.el10uek ELSA-2026-50372

Advisories 44

References