Description
In the Linux kernel, the following vulnerability has been resolved:
NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg
In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already
set by another thread, __nfs4_file_get_access should not be called
to increment the nfs4_file access count since that was already done
by the thread that added READ access to the file. The extra fi_access
count in nfs4_file can prevent the corresponding nfsd_file from being
freed.
When stopping nfs-server service, these extra access counts trigger a
BUG in kmem_cache_destroy() that shows nfsd_file object remaining on
__kmem_cache_shutdown.
This problem can be reproduced by running the Git project's test
suite over NFS.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.18.4 – < 6.18.33, 6.19 | 6.18.33 |
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 | 7.0.10-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | linux | 7.0.0-28.28 | USN-8566-1 |
| Ubuntu 26.04 LTS | linux-aws +2 | 7.0.0-1009.9 | USN-8618-1, USN-8603-1, USN-8568-1 |
| Ubuntu 26.04 LTS | linux-gcp +1 | 7.0.0-1008.8 | USN-8593-1, USN-8566-1 |
| Ubuntu 26.04 LTS | linux-gke | 7.0.0-1003.4 | USN-8566-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1010.10 | USN-8603-1, USN-8593-1 |
| Ubuntu 26.04 LTS | linux-nvidia | 7.0.0-1016.16 | USN-8663-1 |
| Ubuntu 26.04 LTS | linux-nvidia-bos | 7.0.0-2016.16 | USN-8664-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1015.15 | USN-8618-1 |
| Ubuntu 26.04 LTS | linux-riscv +1 | 7.0.0-28.28.1 | USN-8566-1 |
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-azure-7.0 | 7.0.0-1014.14~24.04.1 | USN-8728-2 |
| Ubuntu 24.04 LTS | linux-azure-fde-7.0 | 7.0.0-1013.13~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-gcp-7.0 +1 | 7.0.0-1011.11~24.04.1 | USN-8728-3, USN-8728-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-28.28~24.04.1 | USN-8569-1 |
| Ubuntu 24.04 LTS | linux-nvidia-7.0 | 7.0.0-1016.16~24.04.1 | USN-8663-1 |
| Ubuntu 24.04 LTS | linux-riscv +26 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-7.0 | 7.0.0-28.28.1~24.04.3 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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-realtime-6.14 +1 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | rv +76 | 6.12.0-211.50.1.el10_2 | RHSA-2026:61887 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | rv +74 | 6.12.0-211.50.1.el10_2 | ALSA-2026:61887 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | kernel | 6.12.0-211.50.1.el10_2 | RLSA-2026:61887 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.33-63.124 | 1:1.0-0.amzn2023 | ALAS2023-2026-1866 |
| Amazon Linux 2023 | perf6.18 +11 | 1:6.18.33-63.124.amzn2023 | ALAS2023-2026-1866 |
Advisories 16
- USN-8593-1 linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8663-1 linux-nvidia, linux-nvidia-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8728-1 linux-gcp-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8618-1 linux-aws, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8728-3 linux-oracle-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8728-2 linux-azure-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8603-1 linux-azure, linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8664-1 linux-nvidia-bos vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- RHSA-2026:61887 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2026-2077 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8566-1 linux, linux-gcp, linux-gke, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8569-1 linux-hwe-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8568-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- ALSA-2026:61887 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- RLSA-2026:61887 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 2, 2026
- ALAS2023-2026-1866 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 5, 2026