Skip to content
OpenAdvisories
Unscored CVE-2026-80983 EUVD-2026-76306GHSA-6pmg-4m98-jhww

net/smc: fix socket refcount leak in smc_switch_conns()

Published Sep 11, 2026 · Updated Oct 30, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: kernel Package: linux Package: linux Package: linux-6.12 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-6.14 Package: linux-aws-6.17 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-6.8 Package: linux-aws-7.0 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-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-6.8 Package: linux-azure-7.0 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.15 Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.17 Package: linux-azure-fde-6.2 Package: linux-azure-fde-6.8 Package: linux-azure-fde-7.0 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-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-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-6.8 Package: linux-gcp-7.0 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-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-6.8 Package: linux-hwe-7.0 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-6.11 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-6.17 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-6.8 Package: linux-nvidia-7.0 Package: linux-nvidia-bos 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-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oem-7.0 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-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-6.8 Package: linux-oracle-7.0 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 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-6.17 Package: linux-riscv-6.5 Package: linux-riscv-6.8 Package: linux-riscv-7.0 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:

net/smc: fix socket refcount leak in smc_switch_conns()

smc_switch_conns() takes a reference on the SMC socket before dropping
lgr->conns_lock, so the connection stays alive while the CDC slot is
fetched:

sock_hold(&smc->sk);
read_unlock_bh(&lgr->conns_lock);
/* pre-fetch buffer outside of send_lock, might sleep */
rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
if (rc)
goto err_out;

The err_out label only drops the wr_tx link reference, so this early exit
returns without the matching sock_put(). The second error exit is not
affected, because sock_put() has already run by then.

A leaked sk_refcnt means the smc_sock is never destroyed. Its send and
receive buffers stay allocated, and for a user socket the reference held
on the network namespace is never released, so the netns can no longer be
torn down.

smc_cdc_get_free_slot() fails when the target link goes down or when the
connection has been killed while the switch is in progress. Both are
reachable during the link failover this function implements, so the leak
is triggered by the same hardware events that make smc_switch_conns() run
in the first place.

Restructure so there is a single sock_put() covering both outcomes,
instead of adding a second one to the error path.

Affected products

VendorProductAffectedFixed
Linux Linux 5.10.90 – < 5.10.273, 5.14.14 – < 5.15, 5.15 5.10.273

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 7.2.6-1 —
Debian 13 linux 6.12.111-1 —
Debian 12 linux 6.1.190-1 —
Debian 12 linux-6.12 6.12.111-1~deb12u1 —
ReleasePackageFixed inAdvisory
Ubuntu Nvidia-BlueField 24.04 LTS linux-bluefield 6.8.0-1036.41 —
Ubuntu Nvidia-BlueField 22.04 LTS linux-bluefield 5.15.0-1103.105 —
Ubuntu 26.04 LTS linux 7.0.0-42.42 USN-8959-1
Ubuntu 26.04 LTS linux-aws 7.0.0-1016.17 USN-8959-1
Ubuntu 26.04 LTS linux-azure 7.0.0-1020.21 USN-9019-1
Ubuntu 26.04 LTS linux-azure-fde 7.0.0-1019.19 USN-9020-1
Ubuntu 26.04 LTS linux-gcp 7.0.0-1016.18 USN-8959-1
Ubuntu 26.04 LTS linux-gke 7.0.0-1010.11 USN-9020-1
Ubuntu 26.04 LTS linux-ibm +1 7.0.0-1017.17 USN-8960-1, USN-8959-1
Ubuntu 26.04 LTS linux-nvidia +1 No fix yet —
Ubuntu 26.04 LTS linux-oracle 7.0.0-1015.16 USN-8959-1
Ubuntu 26.04 LTS linux-raspi 7.0.0-1023.23 USN-9021-1
Ubuntu 26.04 LTS linux-realtime 7.0.0-43.43.1 USN-9020-1
Ubuntu 26.04 LTS linux-riscv 7.0.0-42.42.1 —
Ubuntu 24.04 LTS linux 6.8.0-149.149 USN-9022-1
Ubuntu 24.04 LTS linux-aws 6.8.0-1069.74 USN-9022-1
Ubuntu 24.04 LTS linux-aws-7.0 7.0.0-1017.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-azure 6.8.0-1073.82 USN-9022-1
Ubuntu 24.04 LTS linux-azure-fde 6.8.0-1071.78 USN-9039-1
Ubuntu 24.04 LTS linux-azure-fde-7.0 7.0.0-1019.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-gcp 6.8.0-1073.81 USN-9022-1
Ubuntu 24.04 LTS linux-gcp-7.0 7.0.0-1017.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-gke 6.8.0-1068.77 USN-9022-1
Ubuntu 24.04 LTS linux-gkeop 6.8.0-1053.57 USN-9023-1
Ubuntu 24.04 LTS linux-hwe-7.0 7.0.0-42.42~24.04.1 USN-8959-1
Ubuntu 24.04 LTS linux-ibm 6.8.0-1069.70 USN-9022-1
Ubuntu 24.04 LTS linux-lowlatency 6.8.0-149.149.1 USN-9022-1
Ubuntu 24.04 LTS linux-nvidia 6.8.0-1067.70 USN-9024-1
Ubuntu 24.04 LTS linux-nvidia-lowlatency 6.8.0-1067.70.1 USN-9040-1
Ubuntu 24.04 LTS linux-oracle 6.8.0-1067.71 USN-9022-1
Ubuntu 24.04 LTS linux-oracle-7.0 7.0.0-1016.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-raspi 6.8.0-1068.72 USN-9025-1
Ubuntu 24.04 LTS linux-riscv +32 No fix yet —
Ubuntu 24.04 LTS linux-riscv-7.0 7.0.0-42.42.1~24.04.1 —
Ubuntu 24.04 LTS linux-vmware 6.8.0-1010.10 USN-9022-1
Ubuntu 22.04 LTS linux 5.15.0-202.212 USN-8961-1
Ubuntu 22.04 LTS linux-aws 5.15.0-1119.126 USN-8961-1
Ubuntu 22.04 LTS linux-aws-6.8 6.8.0-1069.74~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-azure 5.15.0-1125.134 USN-8961-1
Ubuntu 22.04 LTS linux-azure-6.8 6.8.0-1073.82~22.04.1 USN-9026-1
Ubuntu 22.04 LTS linux-azure-fde 5.15.0-1124.133 USN-8962-1
Ubuntu 22.04 LTS linux-azure-fde-6.8 6.8.0-1071.78~22.04.1 USN-9026-1
Ubuntu 22.04 LTS linux-gcp 5.15.0-1120.130 USN-8961-1
Ubuntu 22.04 LTS linux-gcp-6.8 6.8.0-1073.81~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-gke 5.15.0-1115.121 USN-8961-1
Ubuntu 22.04 LTS linux-gkeop 5.15.0-1102.110 USN-8961-1
Ubuntu 22.04 LTS linux-hwe-6.8 6.8.0-149.149~22.04.1 USN-9066-1
Ubuntu 22.04 LTS linux-ibm 5.15.0-1113.117 USN-8961-1
Ubuntu 22.04 LTS linux-ibm-6.8 6.8.0-1069.70~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-intel-iotg 5.15.0-1114.120 USN-8961-1
Ubuntu 22.04 LTS linux-kvm 5.15.0-1111.116 USN-8961-1
Ubuntu 22.04 LTS linux-lowlatency 5.15.0-197.207 USN-8961-1
Ubuntu 22.04 LTS linux-lowlatency-hwe-6.8 6.8.0-149.149.1~22.04.1 USN-9024-1
Ubuntu 22.04 LTS linux-nvidia 5.15.0-1114.115 USN-8961-1
Ubuntu 22.04 LTS linux-nvidia-tegra 5.15.0-1070.72 USN-8963-1
Ubuntu 22.04 LTS linux-nvidia-tegra-igx 5.15.0-1059.59 USN-8963-1
Ubuntu 22.04 LTS linux-oracle 5.15.0-1116.122 USN-8961-1
Ubuntu 22.04 LTS linux-oracle-6.8 6.8.0-1067.71~22.04.1 USN-9025-1
Ubuntu 22.04 LTS linux-raspi 5.15.0-1113.116 USN-9029-1
Ubuntu 22.04 LTS linux-riscv +34 No fix yet —
Show 9 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 6.8.0-2056.58 USN-9025-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime 6.8.1-1064.65 USN-9023-1
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 +1 No fix yet —
Ubuntu Pro Realtime 22.04 LTS linux-intel-iot-realtime 5.15.0-1111.115 USN-8961-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime 5.15.0-1118.127 USN-8961-1
Ubuntu Pro Realtime 22.04 LTS linux-realtime-6.8 6.8.1-1064.65~22.04.1 USN-9024-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-aws-fips 6.8.0-1069.74+fips1 USN-9023-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-azure-fips 6.8.0-1073.82+fips1 USN-9022-1
Ubuntu Pro FIPS-updates 24.04 LTS linux-fips No fix yet —
Ubuntu Pro FIPS-updates 24.04 LTS linux-gcp-fips 6.8.0-1073.81+fips1 USN-9023-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-aws-fips 5.15.0-1119.126+fips1 USN-8961-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-azure-fips 5.15.0-1125.134+fips1 USN-8961-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-fips 5.15.0-202.212+fips1 USN-8961-1
Ubuntu Pro FIPS-updates 22.04 LTS linux-gcp-fips 5.15.0-1120.130+fips1 USN-8961-1
Ubuntu Pro FIPS-preview 22.04 LTS linux-fips +3 No fix yet —
Ubuntu Pro 20.04 LTS linux-aws-5.15 5.15.0-1119.126~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-azure-5.15 5.15.0-1125.134~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-azure-fde-5.15 5.15.0-1124.133~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-gcp-5.15 5.15.0-1120.130~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-hwe-5.15 5.15.0-202.212~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-ibm-5.15 5.15.0-1113.117~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-intel-iotg-5.15 5.15.0-1114.120~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-lowlatency-hwe-5.15 5.15.0-197.207~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-nvidia-tegra-5.15 5.15.0-1070.72~20.04.1 USN-8963-1
Ubuntu Pro 20.04 LTS linux-oracle-5.15 5.15.0-1116.122~20.04.1 USN-8961-1
Ubuntu Pro 20.04 LTS linux-riscv-5.15 5.15.0-1113.117~20.04.2 —
ReleasePackageFixed inAdvisory
SLES 15 SP7 kernel-64kb +7 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1
SLES 15 SP7 kernel-default-base 6.4.0-150700.53.84.1.150700.17.47.1 SUSE-SU-2026:4706-1
Show 7 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.39.1 SUSE-SU-2026:24235-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.39.1.160000.2.26 SUSE-SU-2026:24235-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.39.1 SUSE-SU-2026:24235-1, SUSE-SU-2026:24197-1
SLES 16.0 kernel-default-base 6.12.0-160000.39.1.160000.2.26 SUSE-SU-2026:24235-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.39.1.160000.2.26 SUSE-SU-2026:24184-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.39.1 SUSE-SU-2026:24184-1, SUSE-SU-2026:24179-1
SLE Micro 6.2 podman 5.4.2-160000.6.1 SUSE-SU-2026:24182-1
SLE Micro 6.1 kernel-default-base 6.4.0-159998.53.1.159998.21.38 SUSE-SU-2026:24181-1
SLE Micro 6.1 kernel-rt +4 6.4.0-159998.53.1 SUSE-SU-2026:24182-1, SUSE-SU-2026:24181-1
SLE Micro 6.0 kernel-default-base 6.4.0-159998.53.1.159998.21.38 SUSE-SU-2026:24315-1
SLE Micro 6.0 kernel-rt +4 6.4.0-159998.53.1 SUSE-SU-2026:24316-1, SUSE-SU-2026:24315-1
SLE Live Patching 15 SP7 kernel-default 6.4.0-150700.53.84.1 SUSE-SU-2026:4706-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7-RT_Update_21 1-150700.1.3.1 SUSE-SU-2026:4640-1
SLE Live Patching 15 SP7 kernel-livepatch-SLE15-SP7_Update_22 1-150700.15.3.1 SUSE-SU-2026:4706-1
SUSE Real Time Module 15 SP7 kernel-rt +2 6.4.0-150700.7.78.1 SUSE-SU-2026:4640-1
ReleasePackageFixed inAdvisory
openSUSE Tumbleweed kernel-source 7.2.6-1.1 openSUSE-SU-2026:11805-1
openSUSE Leap 16.0 kernel-default-base 6.12.0-160000.39.1.160000.2.25 openSUSE-SU-2026:22091-1
openSUSE Leap 16.0 kernel-rt +11 6.12.0-160000.39.1 openSUSE-SU-2026:22091-1

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 kernel 6.6.157.1-1 —

Advisories 30

References