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Unscored CVE-2025-39813 EUVD-2025-29601GHSA-cfrf-hx42-xr6f

ftrace: Fix potential warning in trace_printk_seq during ftrace_dump

Published Sep 16, 2025 · Updated Nov 5, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: kernel 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-6.2 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-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-edge Package: linux-azure-fde 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-6.2 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-6.2 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 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-6.2 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-6.5 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-6.5 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-6.8 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-6.5 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: Azure Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

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

ftrace: Fix potential warning in trace_printk_seq during ftrace_dump

When calling ftrace_dump_one() concurrently with reading trace_pipe,
a WARN_ON_ONCE() in trace_printk_seq() can be triggered due to a race
condition.

The issue occurs because:

CPU0 (ftrace_dump) CPU1 (reader)
echo z > /proc/sysrq-trigger

!trace_empty(&iter)
trace_iterator_reset(&iter) <- len = size = 0
cat /sys/kernel/tracing/trace_pipe
trace_find_next_entry_inc(&iter)
__find_next_entry
ring_buffer_empty_cpu <- all empty
return NULL

trace_printk_seq(&iter.seq)
WARN_ON_ONCE(s->seq.len >= s->seq.size)

In the context between trace_empty() and trace_find_next_entry_inc()
during ftrace_dump, the ring buffer data was consumed by other readers.
This caused trace_find_next_entry_inc to return NULL, failing to populate
`iter.seq`. At this point, due to the prior trace_iterator_reset, both
`iter.seq.len` and `iter.seq.size` were set to 0. Since they are equal,
the WARN_ON_ONCE condition is triggered.

Move the trace_printk_seq() into the if block that checks to make sure the
return value of trace_find_next_entry_inc() is non-NULL in
ftrace_dump_one(), ensuring the 'iter.seq' is properly populated before
subsequent operations.

Affected products

VendorProductAffectedFixed
Linux Linux 2.6.28 5.4.298

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 6.16.5-1 —
Debian 13 linux 6.12.48-1 DSA-6008-1
Debian 12 linux 6.1.153-1 DSA-6009-1
Debian 11 linux 5.10.244-1 DLA-4327-1
Debian 11 linux-6.1 6.1.153-1~deb11u1 DLA-4328-1
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1017.21 —
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield 5.15.0-1081.83 —
Ubuntu 25.10 linux-azure-fde No fix yet —
Ubuntu 24.04 LTS linux 6.8.0-106.106 USN-8095-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1050.53 USN-8095-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1051.57 USN-8125-1
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1058.65 —
Ubuntu 24.04 LTS linux-azure-nvidia 6.8.0-1039.42 —
Ubuntu 24.04 LTS linux-gcp 6.8.0-1052.55 USN-8095-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1048.53 USN-8095-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1035.38 USN-8095-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1049.49 USN-8095-1
Ubuntu 24.04 LTS linux-intel +19 No fix yet —
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-106.106.1 USN-8095-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1049.52 USN-8100-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1049.52.1 USN-8100-1
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1020.20 —
Ubuntu 24.04 LTS linux-oracle 6.8.0-1047.48 USN-8095-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1050.54 USN-8095-5
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1028.29 USN-8261-1
Ubuntu 22.04 LTS linux +1 5.15.0-163.173 USN-7909-1
Ubuntu 22.04 LTS linux-aws 5.15.0-1097.104 USN-7909-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1050.53~22.04.1 USN-8095-4
Ubuntu 22.04 LTS linux-azure 5.15.0-1101.110 USN-7910-2
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1051.57~22.04.1 USN-8126-1
Ubuntu 22.04 LTS linux-azure-fde 5.15.0-1102.111.1 —
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1058.65~22.04.1 —
Ubuntu 22.04 LTS linux-gcp 5.15.0-1097.106 USN-7909-4
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1052.55~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-gke 5.15.0-1093.99 USN-7909-4
Ubuntu 22.04 LTS linux-gkeop 5.15.0-1080.88 USN-7909-4
Ubuntu 22.04 LTS linux-hwe-6.8 +1 6.8.0-106.106~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-ibm +1 5.15.0-1091.94 USN-7909-5, USN-7909-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1049.49~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-intel-iotg 5.15.0-1092.98 USN-7909-1
Ubuntu 22.04 LTS linux-kvm 5.15.0-1089.94 USN-7933-1
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-106.106.1~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1092.93 USN-7909-1
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1049.52~22.04.1 USN-8100-1
Ubuntu 22.04 LTS linux-nvidia-tegra 5.15.0-1049.49 USN-7909-1
Ubuntu 22.04 LTS linux-nvidia-tegra-igx 5.15.0-1038.38 USN-7909-1
Ubuntu 22.04 LTS linux-oracle 5.15.0-1094.100 USN-7909-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1047.48~22.04.1 USN-8095-1
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 22.04 LTS linux-xilinx-zynqmp 5.15.0-1061.65 USN-7909-1
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 6.8.0-2040.41 USN-8095-5
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1045.46 USN-8095-3
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-intel-iot-realtime 5.15.0-1089.91 USN-7909-2
Ubuntu Pro Realtime 22.04 LTS linux-realtime 5.15.0-1096.105 USN-7909-2
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1045.46~22.04.1 USN-8095-3
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 6.8.0-1050.53+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1052.58+fips1 USN-8165-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-106.106+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1052.55+fips1 USN-8095-2
Ubuntu Pro FIPS-updates 22.04 LTS linux-aws-fips 5.15.0-1097.104+fips1 USN-7909-3
Ubuntu Pro FIPS-updates 22.04 LTS linux-azure-fips 5.15.0-1101.110+fips1 USN-7910-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-fips 5.15.0-163.173+fips1 USN-7909-3
Ubuntu Pro FIPS-updates 22.04 LTS linux-gcp-fips 5.15.0-1097.106+fips1 USN-7909-3
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 5.15.0-1097.104~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-azure-5.15 5.15.0-1102.111~20.04.1 USN-7938-1
Ubuntu Pro 20.04 LTS linux-gcp-5.15 5.15.0-1097.106~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-hwe-5.15 +1 5.15.0-163.173~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-ibm-5.15 5.15.0-1091.94~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-intel-iotg-5.15 5.15.0-1092.98~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-nvidia-tegra-5.15 5.15.0-1049.49~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-oracle-5.15 5.15.0-1094.100~20.04.1 USN-7909-1
Ubuntu Pro 20.04 LTS linux-riscv-5.15 5.15.0-1092.96~20.04.1 —
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 +6 6.4.0-150700.53.22.1 SUSE-SU-2026:0447-1, SUSE-SU-2025:4057-1
SLES 15 SP7 kernel-azure +2 6.4.0-150700.20.18.1 SUSE-SU-2026:0472-1, SUSE-SU-2025:4132-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.22.1.150700.17.15.1 SUSE-SU-2026:0447-1, SUSE-SU-2025:4057-1
SLES 15 SP6 kernel-64kb +6 6.4.0-150600.23.78.1 SUSE-SU-2026:0471-1, SUSE-SU-2025:4140-1
SLES 15 SP6 kernel-azure +2 6.4.0-150600.8.55.1 SUSE-SU-2025:4128-1
SLES 15 SP6 kernel-default-base 6.4.0-150600.23.78.1.150600.12.34.2 SUSE-SU-2026:0471-1, SUSE-SU-2025:4140-1
SLES 12 SP5 kernel-syms +2 4.12.14-122.280.1 SUSE-SU-2026:0473-1, SUSE-SU-2025:4189-1
Show 11 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +7 6.12.0-160000.6.1 SUSE-SU-2026:20599-1, SUSE-SU-2025:21139-1
SLES for SAP 16.0 kernel-azure 6.12.0-160000.26.1 SUSE-SU-2026:20599-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.6.1.160000.2.4 SUSE-SU-2026:20599-1, SUSE-SU-2025:21139-1
SLES for SAP 15 SP6 kernel-default-base 6.4.0-150600.23.87.1.150600.12.40.1 SUSE-SU-2026:0471-1
SLES for SAP 15 SP6 kernel-docs +4 6.4.0-150600.23.87.1 SUSE-SU-2026:0471-1
SLES 16.0 kernel-64kb +7 6.12.0-160000.6.1 SUSE-SU-2026:20615-1, SUSE-SU-2026:20599-1, SUSE-SU-2025:21179-1
SLES 16.0 kernel-azure 6.12.0-160000.26.1 SUSE-SU-2026:20599-1
SLES 16.0 kernel-default-base 6.12.0-160000.6.1.160000.2.4 SUSE-SU-2026:20599-1, SUSE-SU-2025:21139-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.6.1.160000.2.4 SUSE-SU-2026:20555-1, SUSE-SU-2025:21074-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.6.1 SUSE-SU-2026:20570-1, SUSE-SU-2026:20560-1, SUSE-SU-2026:20555-1
SLE Micro 6.1 kernel-default-base 6.4.0-36.1.21.13 SUSE-SU-2026:20498-1, SUSE-SU-2025:21056-1
SLE Micro 6.1 kernel-rt +1 6.4.0-38.1 SUSE-SU-2026:20876-1, SUSE-SU-2025:21064-1
SLE Micro 6.1 kernel-source +2 6.4.0-36.1 SUSE-SU-2026:20498-1, SUSE-SU-2025:21056-1
SLE Micro 6.0 kernel-default-base 6.4.0-36.1.21.13 SUSE-SU-2026:20477-1, SUSE-SU-2025:21040-1
SLE Micro 6.0 kernel-rt +1 6.4.0-38.1 SUSE-SU-2026:20845-1, SUSE-SU-2025:21052-1
SLE Micro 6.0 kernel-source +2 6.4.0-36.1 SUSE-SU-2026:20477-1, SUSE-SU-2025:21040-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.22.1 SUSE-SU-2026:0447-1, SUSE-SU-2025:4057-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_6 1-150700.1.3.1 SUSE-SU-2025:4141-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_9 1-150700.1.3.2 SUSE-SU-2026:0587-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_6 +1 1-150700.15.3.1 SUSE-SU-2026:0447-1, SUSE-SU-2025:4057-1
SLE Live Patching 15 SP6 kernel-default 6.4.0-150600.23.78.1 SUSE-SU-2026:0471-1, SUSE-SU-2025:4140-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6-RT_Update_17 1-150600.1.3.1 SUSE-SU-2025:4301-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_17 1-150600.13.5.1 SUSE-SU-2025:4140-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_20 1-150600.13.3.1 SUSE-SU-2026:0471-1
SLE Live Patching 12 SP5 kernel-default 4.12.14-122.280.1 SUSE-SU-2026:0473-1, SUSE-SU-2025:4189-1
SLE Live Patching 12 SP5 kgraft-patch-SLE12-SP5_Update_74 1-8.5.1 SUSE-SU-2025:4189-1
SLE Live Patching 12 SP5 kgraft-patch-SLE12-SP5_Update_77 1-8.3.1 SUSE-SU-2026:0473-1
SUSE Real Time Module 15 SP7 kernel-rt +2 6.4.0-150700.7.22.1 SUSE-SU-2026:0587-1, SUSE-SU-2025:4141-1
SUSE Real Time Module 15 SP6 kernel-rt +3 6.4.0-150600.10.58.1 SUSE-SU-2025:4301-1
ReleasePackageFixed inAdvisory
openSUSE Leap 16.0 kernel-azure 6.12.0-160000.26.1 openSUSE-SU-2026:20287-1
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.6.1.160000.2.4 openSUSE-SU-2026:20287-1, openSUSE-SU-2025:20081-1
openSUSE Leap 16.0 kernel-rt +10 6.12.0-160000.6.1 openSUSE-SU-2026:20287-1, openSUSE-SU-2025:20081-1
openSUSE Leap 15.6 dtb-aarch64 +10 6.4.0-150600.23.78.1 SUSE-SU-2026:0471-1, SUSE-SU-2025:4140-1
openSUSE Leap 15.6 kernel-azure +2 6.4.0-150600.8.55.1 SUSE-SU-2025:4128-1
openSUSE Leap 15.6 kernel-default-base 6.4.0-150600.23.78.1.150600.12.34.2 SUSE-SU-2026:0471-1, SUSE-SU-2025:4140-1
openSUSE Leap 15.6 kernel-rt +3 6.4.0-150600.10.58.1 SUSE-SU-2025:4301-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.12.46-66.121 +1 1:1.0-0.amzn2023 ALAS2023-2025-1208, ALAS2023-2025-1186
Amazon Linux 2023 perf +14 1:6.1.150-174.273.amzn2023 ALAS2023-2025-1186
Amazon Linux 2023 perf6.12 +14 1:6.12.46-66.121.amzn2023 ALAS2023-2025-1208

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.104.2-1 —
Azure Linux 2 (CBL-Mariner) kernel 5.15.200.1-1 —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 9 kernel-uek +34 6.12.0-105.51.5.el10uek ELSA-2025-25754
Oracle Linux 8 bpftool +18 5.15.0-314.193.5.3.el9uek ELSA-2025-25757
Oracle Linux 7 kernel-uek +6 5.4.17-2136.348.3.el8uek ELSA-2025-20663
Oracle Linux 7 kernel-uek-tools 5.4.17-2136.348.3.el7uek ELSA-2025-20663

Advisories 50

References