Unrated severityNVD Advisory· Published Mar 27, 2025· Updated Aug 28, 2025

net: better track kernel sockets lifetime

CVE-2025-21884

Description

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

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

Affected products

Linux/Kernelllm-fuzzy
osv-coords78 versions
pkg:rpm/opensuse/dtb-aarch64&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-64kb&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-azure&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-debug&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-default-base&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-default&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-docs&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-kvmsmall&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-obs-build&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-obs-qa&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-rt_debug&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-rt&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-source-azure&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-source&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-source-rt&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-syms-azure&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-syms&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-syms-rt&distro=openSUSE%20Leap%2015.6 pkg:rpm/opensuse/kernel-zfcpdump&distro=openSUSE%20Leap%2015.6 pkg:rpm/suse/kernel-64kb&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6 pkg:rpm/suse/kernel-64kb&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP7 pkg:rpm/suse/kernel-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6 pkg:rpm/suse/kernel-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP7 pkg:rpm/suse/kernel-coco_debug&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6 pkg:rpm/suse/kernel-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6 pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6 pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP7 pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20High%20Availability%20Extension%2015%20SP6 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20High%20Availability%20Extension%2015%20SP7 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP7 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP7 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Legacy%2015%20SP6 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Legacy%2015%20SP7 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Workstation%20Extension%2015%20SP6 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Workstation%20Extension%2015%20SP7 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-docs&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6 pkg:rpm/suse/kernel-docs&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP7 pkg:rpm/suse/kernel-kvmsmall&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-kvmsmall&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-livepatch-MICRO-6-0-RT_Update_7&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-livepatch-MICRO-6-0-RT_Update_7&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-livepatch-MICRO-6-0_Update_6&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-livepatch-MICRO-6-0_Update_6&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-livepatch-SLE15-SP6-RT_Update_11&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6 pkg:rpm/suse/kernel-livepatch-SLE15-SP6_Update_11&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6 pkg:rpm/suse/kernel-livepatch-SLE15-SP7_Update_1&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP7 pkg:rpm/suse/kernel-obs-build&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6 pkg:rpm/suse/kernel-obs-build&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP7 pkg:rpm/suse/kernel-rt_debug&distro=SUSE%20Real%20Time%20Module%2015%20SP6 pkg:rpm/suse/kernel-rt&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-rt&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6 pkg:rpm/suse/kernel-source-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6 pkg:rpm/suse/kernel-source-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP7 pkg:rpm/suse/kernel-source-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP7 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP7 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Linux%20Micro%206.0 pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Linux%20Micro%206.1 pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6 pkg:rpm/suse/kernel-syms-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6 pkg:rpm/suse/kernel-syms-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP7 pkg:rpm/suse/kernel-syms-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6 pkg:rpm/suse/kernel-syms&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6 pkg:rpm/suse/kernel-syms&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP7 pkg:rpm/suse/kernel-syms-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6 pkg:rpm/suse/kernel-zfcpdump&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6 pkg:rpm/suse/kernel-zfcpdump&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP7
< 6.4.0-150600.23.50.1+ 77 more
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1.150600.12.22.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150700.20.3.1
- (no CPE)range: < 6.4.0-15061.21.coco15sp6.1
- (no CPE)range: < 6.4.0-15061.21.coco15sp6.1
- (no CPE)range: < 6.4.0-150600.23.50.1.150600.12.22.1
- (no CPE)range: < 6.4.0-150700.53.3.1.150700.17.2.1
- (no CPE)range: < 6.4.0-28.1.21.6
- (no CPE)range: < 6.4.0-28.1.21.6
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 1-1.3
- (no CPE)range: < 1-1.3
- (no CPE)range: < 1-3.1
- (no CPE)range: < 1-3.1
- (no CPE)range: < 1-150600.1.3.2
- (no CPE)range: < 1-150600.13.3.1
- (no CPE)range: < 1-150700.15.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-30.1
- (no CPE)range: < 6.4.0-30.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150700.20.3.1
- (no CPE)range: < 6.4.0-15061.21.coco15sp6.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 6.4.0-28.1
- (no CPE)range: < 6.4.0-30.1
- (no CPE)range: < 6.4.0-30.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.8.37.1
- (no CPE)range: < 6.4.0-150700.20.3.1
- (no CPE)range: < 6.4.0-15061.21.coco15sp6.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
- (no CPE)range: < 6.4.0-150600.10.39.1
- (no CPE)range: < 6.4.0-150600.23.50.1
- (no CPE)range: < 6.4.0-150700.53.3.1
Linux/Linuxcpe-rescue
Range: 6.2

Patches

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

News mentions

No linked articles in our index yet.

cvss	0.000
epss	0.000
exploit	0.000
kev	0.000
patch	0.000
ransomware	0.000