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High · 7.8 CVE-2024-47794 EUVD-2024-42878GHSA-qrrc-56f8-gw3j

bpf: Prevent tailcall infinite loop caused by freplace

Published Jan 11, 2025 · Updated Oct 30, 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-5.8 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-fips Package: linux-azure 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-5.8 Package: linux-azure-6.11 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-6.2 Package: linux-azure-fips Package: linux-azure-nvidia Package: linux-bluefield Package: linux-fips Package: linux-gcp 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-5.8 Package: linux-gcp-6.11 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-5.8 Package: linux-hwe-6.11 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-6.8 Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-intel-iotg Package: linux-intel-iotg-5.15 Package: linux-kvm Package: linux-lowlatency Package: linux-lowlatency-hwe-5.15 Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-lowlatency-hwe-6.8 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-6.5 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-5.8 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime 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-6.5 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:

bpf: Prevent tailcall infinite loop caused by freplace

There is a potential infinite loop issue that can occur when using a
combination of tail calls and freplace.

In an upcoming selftest, the attach target for entry_freplace of
tailcall_freplace.c is subprog_tc of tc_bpf2bpf.c, while the tail call in
entry_freplace leads to entry_tc. This results in an infinite loop:

entry_tc -> subprog_tc -> entry_freplace --tailcall-> entry_tc.

The problem arises because the tail_call_cnt in entry_freplace resets to
zero each time entry_freplace is executed, causing the tail call mechanism
to never terminate, eventually leading to a kernel panic.

To fix this issue, the solution is twofold:

1. Prevent updating a program extended by an freplace program to a
prog_array map.
2. Prevent extending a program that is already part of a prog_array map
with an freplace program.

This ensures that:

* If a program or its subprogram has been extended by an freplace program,
it can no longer be updated to a prog_array map.
* If a program has been added to a prog_array map, neither it nor its
subprograms can be extended by an freplace program.

Moreover, an extension program should not be tailcalled. As such, return
-EINVAL if the program has a type of BPF_PROG_TYPE_EXT when adding it to a
prog_array map.

Additionally, fix a minor code style issue by replacing eight spaces with a
tab for proper formatting.

Affected products

VendorProductAffectedFixed
Linux Linux 5.6 6.1.191

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 6.12.5-1 —
Debian 13 linux 6.12.5-1 —
Debian 12 linux No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield No fix yet —
Ubuntu 24.04 LTS linux 6.8.0-58.60 USN-7449-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1027.29 USN-7449-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1027.32 USN-7449-1
Ubuntu 24.04 LTS linux-azure-6.11 6.11.0-1012.12~24.04.1 —
Ubuntu 24.04 LTS linux-azure-nvidia 6.8.0-1014.15 USN-7468-1
Ubuntu 24.04 LTS linux-gcp 6.8.0-1028.30 USN-7450-1
Ubuntu 24.04 LTS linux-gcp-6.11 6.11.0-1011.11~24.04.1 —
Ubuntu 24.04 LTS linux-gke 6.8.0-1023.27 USN-7450-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1010.12 USN-7450-1
Ubuntu 24.04 LTS linux-hwe-6.11 6.11.0-21.21~24.04.1 USN-7379-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1024.24 USN-7449-1
Ubuntu 24.04 LTS linux-lowlatency-hwe-6.11 6.11.0-1011.12~24.04.1 USN-7381-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1026.29 USN-7449-1
Ubuntu 24.04 LTS linux-nvidia-6.11 6.11.0-1007.7 —
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1026.29.1 USN-7449-1
Ubuntu 24.04 LTS linux-nvidia-tegra 6.8.0-1008.8 —
Ubuntu 24.04 LTS linux-oem-6.11 6.11.0-1017.17 USN-7382-1
Ubuntu 24.04 LTS linux-oem-6.8 6.8.0-1026.26 USN-7449-1
Ubuntu 24.04 LTS linux-oracle 6.8.0-1024.25 USN-7449-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1028.32 USN-7524-1
Ubuntu 24.04 LTS linux-realtime +1 No fix yet —
Ubuntu 24.04 LTS linux-riscv +1 6.8.0-58.60.1 USN-7449-1
Ubuntu 24.04 LTS linux-xilinx 6.8.0-1017.18 —
Ubuntu 22.04 LTS linux +49 No fix yet —
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1027.29~22.04.1 USN-7451-1
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1027.32~22.04.1 USN-7449-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1028.30~22.04.1 USN-7452-1
Ubuntu 22.04 LTS linux-hwe-6.8 6.8.0-58.60~22.04.1 USN-7449-2
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1024.24~22.04.1 —
Ubuntu 22.04 LTS linux-nvidia-6.8 6.8.0-1026.29~22.04.1 USN-7449-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1024.25~22.04.1 USN-7449-1
Ubuntu 22.04 LTS linux-riscv-6.8 +1 6.8.0-58.60.1~22.04.1 USN-7449-1
Ubuntu 20.04 LTS linux-gke +28 No fix yet —
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Show 7 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-raspi-realtime 6.8.0-2023.24 USN-7523-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1020.21 USN-7453-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime +1 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1020.21~22.04.1 —
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips 6.8.0-78.78+fips1 —
Ubuntu Pro FIPS-updates 22.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro FIPS-preview 22.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro 20.04 LTS linux-aws-5.15 +10 No fix yet —
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +6 6.4.0-150700.53.3.1 SUSE-SU-2025:01951-1
SLES 15 SP7 kernel-azure +2 6.4.0-150700.20.3.1 SUSE-SU-2025:01967-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.3.1.150700.17.2.1 SUSE-SU-2025:01951-1
SLES 15 SP6 kernel-64kb +3 6.4.0-150600.23.47.2 SUSE-SU-2025:1180-1
SLES 15 SP6 kernel-azure +1 6.4.0-150600.8.34.2 SUSE-SU-2025:1177-1
SLES 15 SP6 kernel-coco +3 6.4.0-15061.21.coco15sp6.1 SUSE-SU-2025:01919-1
SLES 15 SP6 kernel-default-base 6.4.0-150600.23.47.2.150600.12.20.2 SUSE-SU-2025:1180-1
SLES 15 SP6 kernel-docs +2 6.4.0-150600.23.47.1 SUSE-SU-2025:1180-1
SLES 15 SP6 kernel-syms-azure 6.4.0-150600.8.34.1 SUSE-SU-2025:1177-1
Show 5 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLE Micro 6.1 kernel-default-base 6.4.0-28.1.21.6 SUSE-SU-2025:20270-1
SLE Micro 6.1 kernel-livepatch-MICRO-6-0_Update_6 +1 1-3.1 SUSE-SU-2025:20270-1, SUSE-SU-2025:20260-1
SLE Micro 6.1 kernel-rt +4 6.4.0-28.1 SUSE-SU-2025:20270-1, SUSE-SU-2025:20260-1
SLE Micro 6.0 kernel-default-base 6.4.0-28.1.21.6 SUSE-SU-2025:20192-1
SLE Micro 6.0 kernel-livepatch-MICRO-6-0_Update_6 +1 1-3.1 SUSE-SU-2025:20192-1, SUSE-SU-2025:20190-1
SLE Micro 6.0 kernel-rt +4 6.4.0-28.1 SUSE-SU-2025:20192-1, SUSE-SU-2025:20190-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.3.1 SUSE-SU-2025:01951-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_1 1-150700.15.3.1 SUSE-SU-2025:01951-1
SLE Live Patching 15 SP6 kernel-default 6.4.0-150600.23.47.2 SUSE-SU-2025:1180-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6-RT_Update_10 1-150600.1.5.1 SUSE-SU-2025:1178-1
SLE Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_10 1-150600.13.5.1 SUSE-SU-2025:1180-1
SUSE Real Time Module 15 SP6 kernel-rt +3 6.4.0-150600.10.34.1 SUSE-SU-2025:1178-1
ReleasePackageFixed inAdvisory
openSUSE Leap 15.6 dtb-aarch64 +4 6.4.0-150600.23.47.1 SUSE-SU-2025:1180-1
openSUSE Leap 15.6 kernel-64kb +5 6.4.0-150600.23.47.2 SUSE-SU-2025:1180-1
openSUSE Leap 15.6 kernel-azure +1 6.4.0-150600.8.34.2 SUSE-SU-2025:1177-1
openSUSE Leap 15.6 kernel-default-base 6.4.0-150600.23.47.2.150600.12.20.2 SUSE-SU-2025:1180-1
openSUSE Leap 15.6 kernel-rt +3 6.4.0-150600.10.34.1 SUSE-SU-2025:1178-1
openSUSE Leap 15.6 kernel-syms-azure 6.4.0-150600.8.34.1 SUSE-SU-2025:1177-1

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel No fix yet —
Azure Linux 2 (CBL-Mariner) kernel No fix yet —

Oracle Linux

ReleasePackageFixed inAdvisory
Oracle Linux 9 kernel-uek +34 6.12.0-101.33.4.3.el10uek ELSA-2025-20530, ELSA-2025-20480

Advisories 26

References