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: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon_linux_2023 | — | Upgrade kernel-modules-extra-commonUpgrade kernel-libbpf-develUpgrade kernel-libbpf-debuginfoUpgrade bpftoolUpgrade kernel-tools-develUpgrade kernel-develUpgrade python3-perf6.12-debuginfoUpgrade kernel-libbpf-staticUpgrade kernel6.12-debuginfoUpgrade kernel-toolsUpgrade kernel6.12Upgrade kernel-livepatch-6.12.29-33.102Upgrade kernel6.12-debuginfo-common-aarch64Upgrade kernel6.12-debuginfo-common-x86_64Upgrade kernel-headersUpgrade kernel-tools-debuginfoUpgrade python3-perf6.12Upgrade kernel-libbpfUpgrade perf6.12-debuginfoUpgrade kernel6.12-modules-extraUpgrade bpftool-debuginfoUpgrade perf6.12 | Jun 3, 2025 | Mar 27, 2025 |
| Debian | — | Upgrade linux | Jul 23, 2026 | Jul 23, 2026 |
| Oracle_linux | — | Upgrade kernel-uek | Oct 16, 2025 | Mar 27, 2025 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Mar 27, 2025 |
| Suse | — | Upgrade dtb-apmUpgrade dlm-kmp-azureUpgrade dtb-amazonUpgrade kernel-source-azureUpgrade kernel-symsUpgrade kernel-rt-develUpgrade ocfs2-kmp-azureUpgrade dtb-amdUpgrade kernel-azure-extraUpgrade kernel-64kb-optionalUpgrade kselftests-kmp-64kbUpgrade kernel-debugUpgrade kernel-sourceUpgrade reiserfs-kmp-defaultUpgrade dtb-amlogicUpgrade kernel-default-optionalUpgrade dtb-appleUpgrade kernel-zfcpdumpUpgrade dtb-armUpgrade dtb-lgUpgrade dtb-hisiliconUpgrade dtb-mediatekUpgrade dtb-renesasUpgrade kernel-default-extraUpgrade gfs2-kmp-64kbUpgrade kernel-devel-azureUpgrade kernel-obs-qaUpgrade kernel-kvmsmallUpgrade kernel-syms-azureUpgrade kernel-kvmsmall-develUpgrade kernel-devel-rtUpgrade kselftests-kmp-defaultUpgrade kernel-rt-livepatch-develUpgrade kernel-64kb-develUpgrade dtb-socionextUpgrade kernel-azure-vdsoUpgrade kernel-debug-develUpgrade kernel-default-develUpgrade cluster-md-kmp-defaultUpgrade cluster-md-kmp-rtUpgrade kernel-rt_debug-vdsoUpgrade dlm-kmp-64kbUpgrade cluster-md-kmp-azureUpgrade dtb-xilinxUpgrade kernel-syms-rtUpgrade kernel-macrosUpgrade ocfs2-kmp-rtUpgrade kernel-develUpgrade dtb-freescaleUpgrade gfs2-kmp-rtUpgrade kernel-64kbUpgrade dtb-exynosUpgrade kernel-default-vdsoUpgrade gfs2-kmp-azureUpgrade dtb-sprdUpgrade dtb-alteraUpgrade kernel-obs-buildUpgrade dtb-rockchipUpgrade dtb-marvellUpgrade dlm-kmp-defaultUpgrade reiserfs-kmp-64kbUpgrade kernel-source-vanillaUpgrade kernel-rt-optionalUpgrade kernel-docs-htmlUpgrade kernel-defaultUpgrade cluster-md-kmp-64kbUpgrade kernel-docsUpgrade kernel-rt-extraUpgrade kernel-rt_debugUpgrade kselftests-kmp-rtUpgrade kernel-default-base-rebuildUpgrade kernel-azure-develUpgrade gfs2-kmp-defaultUpgrade dlm-kmp-rtUpgrade reiserfs-kmp-azureUpgrade kselftests-kmp-azureUpgrade kernel-64kb-extraUpgrade dtb-qcomUpgrade ocfs2-kmp-64kbUpgrade kernel-rt_debug-develUpgrade kernel-default-baseUpgrade dtb-caviumUpgrade kernel-default-livepatchUpgrade kernel-kvmsmall-vdsoUpgrade dtb-nvidiaUpgrade reiserfs-kmp-rtUpgrade kernel-source-rtUpgrade kernel-default-livepatch-develUpgrade kernel-azure-optionalUpgrade kernel-rtUpgrade kernel-azureUpgrade ocfs2-kmp-defaultUpgrade kernel-rt-vdsoUpgrade dtb-allwinnerUpgrade dtb-broadcomUpgrade kernel-debug-vdso | Dec 5, 2025 | May 21, 2025 |
| Ubuntu | — | Upgrade linux-image-lowlatency-64kUpgrade linux-image-gcp-64k-lts-24.04Upgrade linux-image-gcp-fips-6.8Upgrade linux-image-generic-64kUpgrade linux-image-realtime-6.8.1Upgrade linux-image-6.8.0-1047-gcpUpgrade linux-image-6.8.0-1043-gkeUpgrade linux-image-6.8.0-1044-ibmUpgrade linux-image-6.8.0-1051-azureUpgrade linux-image-oem-22.04Upgrade linux-image-nvidia-lowlatency-64k-6.8Upgrade linux-image-oem-22.04cUpgrade linux-image-nvidia-64k-hwe-22.04Upgrade linux-image-6.8.0-1046-nvidiaUpgrade linux-image-aws-64kUpgrade linux-image-azure-6.8Upgrade linux-image-intel-iot-realtimeUpgrade linux-image-6.8.0-100-generic-64kUpgrade linux-image-oem-22.04dUpgrade linux-image-nvidiaUpgrade linux-image-oracle-lts-24.04Upgrade linux-image-6.8.0-100-lowlatencyUpgrade linux-image-nvidia-lowlatency-64kUpgrade linux-image-nvidia-lowlatency-6.8Upgrade linux-image-lowlatency-64k-6.8Upgrade linux-image-fipsUpgrade linux-image-gcp-64kUpgrade linux-image-gcp-64k-6.8Upgrade linux-image-realtimeUpgrade linux-image-gkeUpgrade linux-image-intel-iotgUpgrade linux-image-xilinx-zynqmpUpgrade linux-image-6.8.0-2037-raspi-realtimeUpgrade linux-image-aws-fipsUpgrade linux-image-raspiUpgrade linux-image-lowlatency-6.8Upgrade linux-image-lowlatency-hwe-22.04Upgrade linux-image-6.8.0-1043-oracleUpgrade linux-image-6.8.0-1046-nvidia-lowlatency-64kUpgrade linux-image-genericUpgrade linux-image-6.8.0-1046-azureUpgrade linux-image-gkeopUpgrade linux-image-nvidia-64k-6.8Upgrade linux-image-xilinx-6.8Upgrade linux-image-raspi-realtime-6.8Upgrade linux-image-virtual-6.8Upgrade linux-image-6.8.0-1030-gkeopUpgrade linux-image-6.8.0-1046-aws-64kUpgrade linux-image-lowlatency-64k-hwe-22.04Upgrade linux-image-nvidia-hwe-22.04Upgrade linux-image-nvidia-6.8Upgrade linux-image-raspi-6.8Upgrade linux-image-generic-lpaeUpgrade linux-image-generic-64k-hwe-22.04Upgrade linux-image-oracleUpgrade linux-image-aws-6.8Upgrade linux-image-realtime-hwe-22.04Upgrade linux-image-aws-lts-24.04Upgrade linux-image-xilinxUpgrade linux-image-lowlatencyUpgrade linux-image-6.8.0-1046-aws-fipsUpgrade linux-image-nvidia-lowlatencyUpgrade linux-image-gkeop-6.8Upgrade linux-image-virtual-hwe-22.04Upgrade linux-image-6.8.0-1047-gcp-64kUpgrade linux-image-ibm-lts-24.04Upgrade linux-image-gcp-6.8Upgrade linux-image-oracle-64k-lts-24.04Upgrade linux-image-fips-6.8Upgrade linux-image-ibm-6.8Upgrade linux-image-ibmUpgrade linux-image-gke-64kUpgrade linux-image-gke-6.8Upgrade linux-image-aws-64k-6.8Upgrade linux-image-6.8.0-1046-nvidia-64kUpgrade linux-image-gcp-fipsUpgrade linux-image-oem-22.04aUpgrade linux-image-6.8.0-100-genericUpgrade linux-image-6.8.0-1047-raspiUpgrade linux-image-aws-64k-lts-24.04Upgrade linux-image-azure-fips-6.8Upgrade linux-image-virtualUpgrade linux-image-6.8.0-1023-xilinxUpgrade linux-image-generic-hwe-22.04Upgrade linux-image-kvmUpgrade linux-image-azureUpgrade linux-image-oracle-64k-6.8Upgrade linux-image-oracle-6.8Upgrade linux-image-nvidia-64kUpgrade linux-image-generic-64k-6.8Upgrade linux-image-gke-64k-6.8Upgrade linux-image-6.8.0-100-lowlatency-64kUpgrade linux-image-6.8.1-1041-realtimeUpgrade linux-image-awsUpgrade linux-image-gcp-lts-24.04Upgrade linux-image-gcpUpgrade linux-image-6.8.0-1046-nvidia-lowlatencyUpgrade linux-image-6.8.0-100-fipsUpgrade linux-image-6.8.0-1046-awsUpgrade linux-image-raspi-realtimeUpgrade linux-image-azure-lts-24.04Upgrade linux-image-azure-fipsUpgrade linux-image-6.8.0-1047-gcp-fipsUpgrade linux-image-oracle-64kUpgrade linux-image-6.8.0-1043-oracle-64kUpgrade linux-image-generic-6.8Upgrade linux-image-6.8.0-1043-gke-64kUpgrade linux-image-ibm-classicUpgrade linux-image-aws-fips-6.8Upgrade linux-image-6.8.0-1046-azure-fipsUpgrade linux-image-oem-22.04b | Jun 26, 2025 | Mar 27, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jul 17, 2026 | Mar 27, 2025 |
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