In the Linux kernel, the following vulnerability has been resolved:
net: better track kernel sockets lifetime
While kernel sockets are dismantled during pernet_operations->exit(), their freeing can be delayed by any tx packets still held in qdisc or device queues, due to skb_set_owner_w() prior calls.
This then trigger the following warning from ref_tracker_dir_exit() [1]
To fix this, make sure that kernel sockets own a reference on net->passive.
Add sk_net_refcnt_upgrade() helper, used whenever a kernel socket is converted to a refcounted one.
[1]
[ 136.263918][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.263918][ T35] sk_alloc+0x2b3/0x370 [ 136.263918][ T35] inet6_create+0x6ce/0x10f0 [ 136.263918][ T35] __sock_create+0x4c0/0xa30 [ 136.263918][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.263918][ T35] igmp6_net_init+0x39/0x390 [ 136.263918][ T35] ops_init+0x31e/0x590 [ 136.263918][ T35] setup_net+0x287/0x9e0 [ 136.263918][ T35] copy_net_ns+0x33f/0x570 [ 136.263918][ T35] create_new_namespaces+0x425/0x7b0 [ 136.263918][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.263918][ T35] ksys_unshare+0x57d/0xa70 [ 136.263918][ T35] __x64_sys_unshare+0x38/0x40 [ 136.263918][ T35] do_syscall_64+0xf3/0x230 [ 136.263918][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 136.263918][ T35] [ 136.343488][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.343488][ T35] sk_alloc+0x2b3/0x370 [ 136.343488][ T35] inet6_create+0x6ce/0x10f0 [ 136.343488][ T35] __sock_create+0x4c0/0xa30 [ 136.343488][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.343488][ T35] ndisc_net_init+0xa7/0x2b0 [ 136.343488][ T35] ops_init+0x31e/0x590 [ 136.343488][ T35] setup_net+0x287/0x9e0 [ 136.343488][ T35] copy_net_ns+0x33f/0x570 [ 136.343488][ T35] create_new_namespaces+0x425/0x7b0 [ 136.343488][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.343488][ T35] ksys_unshare+0x57d/0xa70 [ 136.343488][ T35] __x64_sys_unshare+0x38/0x40 [ 136.343488][ T35] do_syscall_64+0xf3/0x230 [ 136.343488][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f
CVSS Details
- CVSS 3.1 Base Score: 5.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon_linux_2023 | amazon-linux-2023-upgrade-bpftoolamazon-linux-2023-upgrade-bpftool-debuginfoamazon-linux-2023-upgrade-kernel6-12amazon-linux-2023-upgrade-kernel6-12-debuginfoamazon-linux-2023-upgrade-kernel6-12-debuginfo-common-aarch64amazon-linux-2023-upgrade-kernel6-12-debuginfo-common-x86-64amazon-linux-2023-upgrade-kernel6-12-modules-extraamazon-linux-2023-upgrade-kernel-develamazon-linux-2023-upgrade-kernel-headersamazon-linux-2023-upgrade-kernel-libbpfamazon-linux-2023-upgrade-kernel-libbpf-debuginfoamazon-linux-2023-upgrade-kernel-libbpf-develamazon-linux-2023-upgrade-kernel-libbpf-staticamazon-linux-2023-upgrade-kernel-livepatch-6-12-29-33-102amazon-linux-2023-upgrade-kernel-modules-extra-commonamazon-linux-2023-upgrade-kernel-toolsamazon-linux-2023-upgrade-kernel-tools-debuginfoamazon-linux-2023-upgrade-kernel-tools-develamazon-linux-2023-upgrade-perf6-12amazon-linux-2023-upgrade-perf6-12-debuginfoamazon-linux-2023-upgrade-python3-perf6-12amazon-linux-2023-upgrade-python3-perf6-12-debuginfo | Jun 3, 2025 | Mar 27, 2025 | |
| Oracle_linux | — | oracle-linux-upgrade-kernel-uek | Oct 16, 2025 | Mar 27, 2025 |
| Redhat_linux | — | no-fix-redhat-rpm-package | Jul 9, 2025 | Mar 27, 2025 |
| Suse | — | suse-upgrade-cluster-md-kmp-64kbsuse-upgrade-cluster-md-kmp-azuresuse-upgrade-cluster-md-kmp-defaultsuse-upgrade-cluster-md-kmp-rtsuse-upgrade-dlm-kmp-64kbsuse-upgrade-dlm-kmp-azuresuse-upgrade-dlm-kmp-defaultsuse-upgrade-dlm-kmp-rtsuse-upgrade-dtb-allwinnersuse-upgrade-dtb-alterasuse-upgrade-dtb-amazonsuse-upgrade-dtb-amdsuse-upgrade-dtb-amlogicsuse-upgrade-dtb-apmsuse-upgrade-dtb-applesuse-upgrade-dtb-armsuse-upgrade-dtb-broadcomsuse-upgrade-dtb-caviumsuse-upgrade-dtb-exynossuse-upgrade-dtb-freescalesuse-upgrade-dtb-hisiliconsuse-upgrade-dtb-lgsuse-upgrade-dtb-marvellsuse-upgrade-dtb-mediateksuse-upgrade-dtb-nvidiasuse-upgrade-dtb-qcomsuse-upgrade-dtb-renesassuse-upgrade-dtb-rockchipsuse-upgrade-dtb-socionextsuse-upgrade-dtb-sprdsuse-upgrade-dtb-xilinxsuse-upgrade-gfs2-kmp-64kbsuse-upgrade-gfs2-kmp-azuresuse-upgrade-gfs2-kmp-defaultsuse-upgrade-gfs2-kmp-rtsuse-upgrade-kernel-64kbsuse-upgrade-kernel-64kb-develsuse-upgrade-kernel-64kb-extrasuse-upgrade-kernel-64kb-optionalsuse-upgrade-kernel-azuresuse-upgrade-kernel-azure-develsuse-upgrade-kernel-azure-extrasuse-upgrade-kernel-azure-optionalsuse-upgrade-kernel-azure-vdsosuse-upgrade-kernel-debugsuse-upgrade-kernel-debug-develsuse-upgrade-kernel-debug-vdsosuse-upgrade-kernel-defaultsuse-upgrade-kernel-default-basesuse-upgrade-kernel-default-base-rebuildsuse-upgrade-kernel-default-develsuse-upgrade-kernel-default-extrasuse-upgrade-kernel-default-livepatchsuse-upgrade-kernel-default-livepatch-develsuse-upgrade-kernel-default-optionalsuse-upgrade-kernel-default-vdsosuse-upgrade-kernel-develsuse-upgrade-kernel-devel-azuresuse-upgrade-kernel-devel-rtsuse-upgrade-kernel-docssuse-upgrade-kernel-docs-htmlsuse-upgrade-kernel-kvmsmallsuse-upgrade-kernel-kvmsmall-develsuse-upgrade-kernel-kvmsmall-vdsosuse-upgrade-kernel-macrossuse-upgrade-kernel-obs-buildsuse-upgrade-kernel-obs-qasuse-upgrade-kernel-rtsuse-upgrade-kernel-rt-develsuse-upgrade-kernel-rt-extrasuse-upgrade-kernel-rt-livepatch-develsuse-upgrade-kernel-rt-optionalsuse-upgrade-kernel-rt-vdsosuse-upgrade-kernel-rt_debugsuse-upgrade-kernel-rt_debug-develsuse-upgrade-kernel-rt_debug-vdsosuse-upgrade-kernel-sourcesuse-upgrade-kernel-source-azuresuse-upgrade-kernel-source-rtsuse-upgrade-kernel-source-vanillasuse-upgrade-kernel-symssuse-upgrade-kernel-syms-azuresuse-upgrade-kernel-syms-rtsuse-upgrade-kernel-zfcpdumpsuse-upgrade-kselftests-kmp-64kbsuse-upgrade-kselftests-kmp-azuresuse-upgrade-kselftests-kmp-defaultsuse-upgrade-kselftests-kmp-rtsuse-upgrade-ocfs2-kmp-64kbsuse-upgrade-ocfs2-kmp-azuresuse-upgrade-ocfs2-kmp-defaultsuse-upgrade-ocfs2-kmp-rtsuse-upgrade-reiserfs-kmp-64kbsuse-upgrade-reiserfs-kmp-azuresuse-upgrade-reiserfs-kmp-defaultsuse-upgrade-reiserfs-kmp-rt | Dec 5, 2025 | May 21, 2025 |
| Ubuntu | ubuntu-upgrade-linux-image-6-8-0-100-fipsubuntu-upgrade-linux-image-6-8-0-100-genericubuntu-upgrade-linux-image-6-8-0-100-generic-64kubuntu-upgrade-linux-image-6-8-0-100-lowlatencyubuntu-upgrade-linux-image-6-8-0-100-lowlatency-64kubuntu-upgrade-linux-image-6-8-0-1023-xilinxubuntu-upgrade-linux-image-6-8-0-1030-gkeopubuntu-upgrade-linux-image-6-8-0-1043-gkeubuntu-upgrade-linux-image-6-8-0-1043-gke-64kubuntu-upgrade-linux-image-6-8-0-1043-oracleubuntu-upgrade-linux-image-6-8-0-1043-oracle-64kubuntu-upgrade-linux-image-6-8-0-1044-ibmubuntu-upgrade-linux-image-6-8-0-1046-awsubuntu-upgrade-linux-image-6-8-0-1046-aws-64kubuntu-upgrade-linux-image-6-8-0-1046-aws-fipsubuntu-upgrade-linux-image-6-8-0-1046-azureubuntu-upgrade-linux-image-6-8-0-1046-azure-fipsubuntu-upgrade-linux-image-6-8-0-1046-nvidiaubuntu-upgrade-linux-image-6-8-0-1046-nvidia-64kubuntu-upgrade-linux-image-6-8-0-1046-nvidia-lowlatencyubuntu-upgrade-linux-image-6-8-0-1046-nvidia-lowlatency-64kubuntu-upgrade-linux-image-6-8-0-1047-gcpubuntu-upgrade-linux-image-6-8-0-1047-gcp-64kubuntu-upgrade-linux-image-6-8-0-1047-gcp-fipsubuntu-upgrade-linux-image-6-8-0-1047-raspiubuntu-upgrade-linux-image-6-8-0-1051-azureubuntu-upgrade-linux-image-6-8-0-2037-raspi-realtimeubuntu-upgrade-linux-image-6-8-1-1041-realtimeubuntu-upgrade-linux-image-awsubuntu-upgrade-linux-image-aws-6-8ubuntu-upgrade-linux-image-aws-64kubuntu-upgrade-linux-image-aws-64k-6-8ubuntu-upgrade-linux-image-aws-64k-lts-24-04ubuntu-upgrade-linux-image-aws-fipsubuntu-upgrade-linux-image-aws-fips-6-8ubuntu-upgrade-linux-image-aws-lts-24-04ubuntu-upgrade-linux-image-azureubuntu-upgrade-linux-image-azure-6-8ubuntu-upgrade-linux-image-azure-fipsubuntu-upgrade-linux-image-azure-fips-6-8ubuntu-upgrade-linux-image-azure-lts-24-04ubuntu-upgrade-linux-image-fipsubuntu-upgrade-linux-image-fips-6-8ubuntu-upgrade-linux-image-gcpubuntu-upgrade-linux-image-gcp-6-8ubuntu-upgrade-linux-image-gcp-64kubuntu-upgrade-linux-image-gcp-64k-6-8ubuntu-upgrade-linux-image-gcp-64k-lts-24-04ubuntu-upgrade-linux-image-gcp-fipsubuntu-upgrade-linux-image-gcp-fips-6-8ubuntu-upgrade-linux-image-gcp-lts-24-04ubuntu-upgrade-linux-image-genericubuntu-upgrade-linux-image-generic-6-8ubuntu-upgrade-linux-image-generic-64kubuntu-upgrade-linux-image-generic-64k-6-8ubuntu-upgrade-linux-image-generic-64k-hwe-22-04ubuntu-upgrade-linux-image-generic-hwe-22-04ubuntu-upgrade-linux-image-generic-lpaeubuntu-upgrade-linux-image-gkeubuntu-upgrade-linux-image-gke-6-8ubuntu-upgrade-linux-image-gke-64kubuntu-upgrade-linux-image-gke-64k-6-8ubuntu-upgrade-linux-image-gkeopubuntu-upgrade-linux-image-gkeop-6-8ubuntu-upgrade-linux-image-ibmubuntu-upgrade-linux-image-ibm-6-8ubuntu-upgrade-linux-image-ibm-classicubuntu-upgrade-linux-image-ibm-lts-24-04ubuntu-upgrade-linux-image-intel-iot-realtimeubuntu-upgrade-linux-image-intel-iotgubuntu-upgrade-linux-image-kvmubuntu-upgrade-linux-image-lowlatencyubuntu-upgrade-linux-image-lowlatency-6-8ubuntu-upgrade-linux-image-lowlatency-64kubuntu-upgrade-linux-image-lowlatency-64k-6-8ubuntu-upgrade-linux-image-lowlatency-64k-hwe-22-04ubuntu-upgrade-linux-image-lowlatency-hwe-22-04ubuntu-upgrade-linux-image-nvidiaubuntu-upgrade-linux-image-nvidia-6-8ubuntu-upgrade-linux-image-nvidia-64kubuntu-upgrade-linux-image-nvidia-64k-6-8ubuntu-upgrade-linux-image-nvidia-64k-hwe-22-04ubuntu-upgrade-linux-image-nvidia-hwe-22-04ubuntu-upgrade-linux-image-nvidia-lowlatencyubuntu-upgrade-linux-image-nvidia-lowlatency-6-8ubuntu-upgrade-linux-image-nvidia-lowlatency-64kubuntu-upgrade-linux-image-nvidia-lowlatency-64k-6-8ubuntu-upgrade-linux-image-oem-22-04ubuntu-upgrade-linux-image-oem-22-04aubuntu-upgrade-linux-image-oem-22-04bubuntu-upgrade-linux-image-oem-22-04cubuntu-upgrade-linux-image-oem-22-04dubuntu-upgrade-linux-image-oracleubuntu-upgrade-linux-image-oracle-6-8ubuntu-upgrade-linux-image-oracle-64kubuntu-upgrade-linux-image-oracle-64k-6-8ubuntu-upgrade-linux-image-oracle-64k-lts-24-04ubuntu-upgrade-linux-image-oracle-lts-24-04ubuntu-upgrade-linux-image-raspiubuntu-upgrade-linux-image-raspi-6-8ubuntu-upgrade-linux-image-raspi-realtimeubuntu-upgrade-linux-image-raspi-realtime-6-8ubuntu-upgrade-linux-image-realtimeubuntu-upgrade-linux-image-realtime-6-8-1ubuntu-upgrade-linux-image-realtime-hwe-22-04ubuntu-upgrade-linux-image-virtualubuntu-upgrade-linux-image-virtual-6-8ubuntu-upgrade-linux-image-virtual-hwe-22-04ubuntu-upgrade-linux-image-xilinxubuntu-upgrade-linux-image-xilinx-6-8ubuntu-upgrade-linux-image-xilinx-zynqmp | Jun 26, 2025 | Mar 27, 2025 |
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