Description
In the Linux kernel, the following vulnerability has been resolved:
cachefiles: fix dentry leak in cachefiles_open_file()
A dentry leak may be caused when a lookup cookie and a cull are concurrent:
P1 | P2
-----------------------------------------------------------
cachefiles_lookup_cookie
cachefiles_look_up_object
lookup_one_positive_unlocked
// get dentry
cachefiles_cull
inode->i_flags |= S_KERNEL_FILE;
cachefiles_open_file
cachefiles_mark_inode_in_use
__cachefiles_mark_inode_in_use
can_use = false
if (!(inode->i_flags & S_KERNEL_FILE))
can_use = true
return false
return false
// Returns an error but doesn't put dentry
After that the following WARNING will be triggered when the backend folder
is umounted:
==================================================================
BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} still in use (1) [unmount of ext4 sda]
WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70
CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25
RIP: 0010:umount_check+0x5d/0x70
Call Trace:
<TASK>
d_walk+0xda/0x2b0
do_one_tree+0x20/0x40
shrink_dcache_for_umount+0x2c/0x90
generic_shutdown_super+0x20/0x160
kill_block_super+0x1a/0x40
ext4_kill_sb+0x22/0x40
deactivate_locked_super+0x35/0x80
cleanup_mnt+0x104/0x160
==================================================================
Whether cachefiles_open_file() returns true or false, the reference count
obtained by lookup_positive_unlocked() in cachefiles_look_up_object()
should be released.
Therefore release that reference count in cachefiles_look_up_object() to
fix the above issue and simplify the code.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.17 | 6.1.113 |
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 | 6.11.4-1 | — |
| Debian 13 | linux | 6.11.4-1 | — |
| Debian 12 | linux | 6.1.115-1 | — |
| Debian 11 | linux-6.1 | 6.1.119-1~deb11u1 | DLA-4008-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux | 6.8.0-54.56 | USN-7301-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1023.25 | USN-7311-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1025.30 | USN-7384-1 |
| Ubuntu 24.04 LTS | linux-azure-6.11 | 6.11.0-1012.12~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1014.15 | USN-7468-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1024.26 | USN-7304-1 |
| Ubuntu 24.04 LTS | linux-gcp-6.11 | 6.11.0-1011.11~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-gke +1 | 6.8.0-1019.23 | USN-7304-1, USN-7303-3 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1006.8 | USN-7304-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1022.22 | USN-7385-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-54.56.1 | USN-7301-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1022.25 | USN-7303-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.11 | 6.11.0-1007.7 | — |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1022.25.2 | USN-7303-1 |
| Ubuntu 24.04 LTS | linux-oem-6.11 | 6.11.0-1015.15 | USN-7310-1 |
| Ubuntu 24.04 LTS | linux-oem-6.8 | 6.8.0-1024.24 | USN-7386-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1020.21 | USN-7303-2 |
| Ubuntu 24.04 LTS | linux-realtime | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv | 6.8.0-53.55.1 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1017.18 | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1023.25~22.04.1 | USN-7311-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1025.30~22.04.1 | USN-7384-2 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1024.26~22.04.1 | USN-7303-3 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-57.59~22.04.1 | USN-7403-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1023.23~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-54.56.1~22.04.1 | USN-7301-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1022.25~22.04.2 | USN-7303-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1020.21~22.04.1 | USN-7303-2 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-53.55.1~22.04.1 | — |
| 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 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2018.19 | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1016.17 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1016.17~22.04.1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-78.78+fips1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | rv +77 | 5.14.0-570.12.1.el9_6 | RHSA-2025:6966 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| SLES 15 SP6 | kernel-azure | 6.4.0-150600.8.17.2 | SUSE-SU-2024:3984-1 |
| SLES 15 SP6 | kernel-coco +3 | 6.4.0-15061.9.coco15sp6.1 | SUSE-SU-2024:4387-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.30.1.150600.12.12.6 | SUSE-SU-2024:4318-1 |
| SLES 15 SP6 | kernel-syms-azure +1 | 6.4.0-150600.8.17.1 | SUSE-SU-2024:3984-1 |
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLES 15 SP5 | kernel-azure +2 | 5.14.21-150500.33.75.1 | SUSE-SU-2024:4376-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.88.1.150500.6.39.4 | SUSE-SU-2024:4364-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-24.1.21.4 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0-RT_Update_4 | 1-1.1 | SUSE-SU-2025:20246-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0_Update_4 | 1-1.2 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-22.1 | SUSE-SU-2025:20246-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-24.1 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-24.1.21.4 | SUSE-SU-2025:20164-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0-RT_Update_4 | 1-1.1 | SUSE-SU-2025:20163-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0_Update_4 | 1-1.2 | SUSE-SU-2025:20164-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-22.1 | SUSE-SU-2025:20163-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-24.1 | SUSE-SU-2025:20164-1 |
| SLE Micro 5.5 | kernel-default | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.88.1.150500.6.39.4 | SUSE-SU-2024:4364-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_5 | 1-150600.1.3.1 | SUSE-SU-2024:3986-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_6 | 1-150600.13.3.5 | SUSE-SU-2024:4318-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5-RT_Update_23 | 1-150500.11.3.1 | SUSE-SU-2024:4315-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_21 | 1-150500.11.5.1 | SUSE-SU-2024:4364-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.17.1 | SUSE-SU-2024:3986-1 |
| SUSE Real Time Module 15 SP5 | kernel-rt +3 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 6.11.8-1.1 | openSUSE-SU-2024:14500-1 |
| openSUSE Tumbleweed | kernel-source-longterm | 6.12.11-1.1 | openSUSE-SU-2025:14705-1 |
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| openSUSE Leap 15.6 | kernel-azure | 6.4.0-150600.8.17.2 | SUSE-SU-2024:3984-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.30.1.150600.12.12.6 | SUSE-SU-2024:4318-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.17.1 | SUSE-SU-2024:3986-1 |
| openSUSE Leap 15.6 | kernel-syms-azure +1 | 6.4.0-150600.8.17.1 | SUSE-SU-2024:3984-1 |
| openSUSE Leap 15.5 | kernel-azure +2 | 5.14.21-150500.33.75.1 | SUSE-SU-2024:4376-1 |
| openSUSE Leap 15.5 | kernel-rt +3 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap Micro 5.5 | kernel-rt | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.1.115-126.197 | 1.0-0.amzn2023 | ALAS2023-2025-794 |
| Amazon Linux 2023 | perf +14 | 6.1.115-126.197.amzn2023 | ALAS2023-2025-794 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | bpftool | 7.5.0-802.el9_6 | ELSA-2025-6966 |
| Oracle Linux 9 | rv +28 | 5.14.0-570.12.1.0.1.el9_6 | ELSA-2025-6966 |
Advisories 32
- RHSA-2025:6966 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2024-3251 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 11, 2026
- USN-7468-1 linux-azure-nvidia vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7310-1 linux-oem-6.11 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7384-2 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7384-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7386-1 linux-oem-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7304-1 linux-gcp, linux-gke, linux-gkeop vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7303-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7301-1 linux, linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7403-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7303-2 linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7311-1 linux-aws, linux-aws-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7385-1 linux-ibm vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7303-3 linux-gcp-6.8, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- WID-SEC-2025-2855 IBM DataPower Gateway: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 17, 2026
- SUSE-SU-2025:20163-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20246-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20164-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20247-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- DLA-4008-1 linux-6.1 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2024:4376-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4318-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:3984-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:3986-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4364-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2025:14705-1 kernel-devel-longterm-6.12.11-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14500-1 kernel-devel-6.11.8-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4315-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4387-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ALAS2023-2025-794 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 2, 2025
- ELSA-2025-6966 Moderate: kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · May 16, 2025
References
- https://git.kernel.org/stable/c/d32ff64c872d7e08e893c32ba6a2374583444410
- https://git.kernel.org/stable/c/c7d10fa7d7691558ff967668494672415f5fa151
- https://git.kernel.org/stable/c/e4a28489b310339b2b8187bec0a437709be551c1
- https://git.kernel.org/stable/c/7fa2382f97421978514a419c93054eca69f5247b
- https://git.kernel.org/stable/c/da6ef2dffe6056aad3435e6cf7c6471c2a62187c