Description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: guard nfsd_serv deref in nfsd_file_net_dispose
nfsd_file_net_dispose() is the consumer side of l->freeme: the nfsd
service thread loop calls it to drain entries that the filecache
garbage collector and shrinker append via
nfsd_file_dispose_list_delayed(). During per-net teardown,
nn->nfsd_serv is cleared before the filecache laundrette is shut
down, so the service thread can still run a dispose pass that finds
more than eight entries on l->freeme and dereferences a NULL
svc_serv:
nfsd service thread loop
nfsd_file_net_dispose(nn)
if (!list_empty(&l->freeme)) {
...
svc_wake_up(nn->nfsd_serv); /* nn->nfsd_serv == NULL */
}
The sibling helper nfsd_file_dispose_list_delayed() already documents
this ordering and caches nn->nfsd_serv into a local before testing it
for NULL. nfsd_file_net_dispose() was introduced with the same raw
svc_wake_up(nn->nfsd_serv) call and never picked up the guard.
Fix by loading nn->nfsd_serv into a local svc_serv pointer and only
calling svc_wake_up() when it is non-NULL, matching the pattern in
nfsd_file_dispose_list_delayed().
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.9 | 6.12.109 |
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 7.2.6-1 | — |
| Debian 13 | linux | 6.12.111-1 | — |
| Debian 12 | linux-6.12 | 6.12.111-1~deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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-aws-7.0 | 7.0.0-1017.18~24.04.1 | USN-9020-1 |
| 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-7.0 | 7.0.0-1017.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | USN-8959-1 |
| Ubuntu 24.04 LTS | linux-oracle-7.0 | 7.0.0-1016.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-riscv +29 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.2.8-1.1 | openSUSE-SU-2026:11893-1 |
| openSUSE Leap 16.1 | kernel-default-base | 6.12.0-160100.9.1.160100.3.14 | openSUSE-SU-2026:22309-1 |
| openSUSE Leap 16.1 | kernel-nvidia64kb +2 | 6.12.0-160100.6.1 | openSUSE-SU-2026:22313-1 |
| openSUSE Leap 16.1 | kernel-rt +11 | 6.12.0-160100.9.1 | openSUSE-SU-2026:22309-1 |
| 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 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.51-120.162 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-3196, ALAS2023-2026-3187 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.110-135.201.amzn2023 | ALAS2023-2026-3196 |
| Amazon Linux 2023 | perf6.18 +12 | 1:6.18.51-120.162.amzn2023 | ALAS2023-2026-3187 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-207.111.5.1.el10uek | ELSA-2026-500374 |
Advisories 23
- openSUSE-SU-2026:22313-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 14, 2026
- openSUSE-SU-2026:22309-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Nov 14, 2026
- USN-9020-1 linux-aws-7.0, linux-azure-fde, linux-azure-fde-7.0, linux-gcp-7.0, linux-gke, linux-oracle-7.0, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8959-1 linux, linux-aws, linux-gcp, linux-hwe-7.0, linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-9021-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-9019-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8960-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- WID-SEC-2026-3579 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SUSE-SU-2026:24315-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 27, 2026
- SUSE-SU-2026:24316-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 27, 2026
- SUSE-SU-2026:24235-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 21, 2026
- SUSE-SU-2026:24197-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 21, 2026
- ALAS2023-2026-3196 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 21, 2026
- SUSE-SU-2026:24184-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:24179-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:24181-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:24182-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- openSUSE-SU-2026:22091-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 19, 2026
- SUSE-SU-2026:4706-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 17, 2026
- SUSE-SU-2026:4640-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 14, 2026
- ALAS2023-2026-3187 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 12, 2026
- ELSA-2026-500374 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 7, 2026
- openSUSE-SU-2026:11893-1 kernel-devel-7.2.8-1.1 on GA media SUSE / openSUSE Security Updates · Sep 29, 2026