CVE-2025-21981: linux kernel — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: ice: fix memory leak in aRFS after reset Fix aRFS (accelerated Receive Flow Steering) structures memory leak by adding a checker to verify if aRFS memory is already allocated while configuring VSI. aRFS objects are allocated in two cases: - as part of VSI initialization (at probe), and - as part of reset handling However, VSI reconfiguration executed during reset involves memory allocation one more time, without prior releasing already allocated resources. This led to the memory leak with the following signature: [root@os-delivery ~]# cat /sys/kernel/debug/kmemleak unreferenced object 0xff3c1ca7252e6000 (size 8192): comm "kworker/0:0", pid 8, jiffies 4296833052 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<ffffffff991ec485>] __kmalloc_cache_noprof+0x275/0x340 [<ffffffffc0a6e06a>] ice_init_arfs+0x3a/0xe0 [ice] [<ffffffffc09f1027>] ice_vsi_cfg_def+0x607/0x850 [ice] [<ffffffffc09f244b>] ice_vsi_setup+0x5b/0x130 [ice] [<ffffffffc09c2131>] ice_init+0x1c1/0x460 [ice] [<ffffffffc09c64af>] ice_probe+0x2af/0x520 [ice] [<ffffffff994fbcd3>] local_pci_probe+0x43/0xa0 [<ffffffff98f07103>] work_for_cpu_fn+0x13/0x20 [<ffffffff98f0b6d9>] process_one_work+0x179/0x390 [<ffffffff98f0c1e9>] worker_thread+0x239/0x340 [<ffffffff98f14abc>] kthread+0xcc/0x100 [<ffffffff98e45a6d>] ret_from_fork+0x2d/0x50 [<ffffffff98e083ba>] ret_from_fork_asm+0x1a/0x30 ...

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-401 CWE-401

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.8 — 6.1.132
linux	linux_kernel	6.2 — 6.6.84
linux	linux_kernel	6.7 — 6.12.20
linux	linux_kernel	6.13 — 6.13.8
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/23d97f18901ef5e4e264e3b1777fe65c760186b5 https://git.kernel.org/stable/c/3b27e6e10a32589fcd293b8933ab6de9387a460e https://git.kernel.org/stable/c/5d30d256661fc11b6e73fac6c3783a702e1006a3 https://git.kernel.org/stable/c/78f3d64b30210c0e521c59357431aca14024cb79 https://git.kernel.org/stable/c/e6902101f34f098af59b0d1d8cf90c4124c02c6a https://git.kernel.org/stable/c/ef2bc94059836a115430a6ad9d2838b0b34dc8f5 https://git.kernel.org/stable/c/fcbacc47d16306c87ad1b820b7a575f6e9eae58b

Other References

https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html

Frequently Asked Questions

What is CVE-2025-21981? +

In the Linux kernel, the following vulnerability has been resolved: ice: fix memory leak in aRFS after reset Fix aRFS (accelerated Receive Flow Steering) structures memory leak by adding a checker to verify if aRFS memory is already allocated while configuring VSI. aRFS objects are allocated in two cases: - as part of VSI initialization (at probe), and - as part of reset handling However, VSI reconfiguration executed during reset involves memory allocation one more time, without prior releasing already allocated resources. This led to the memory leak with the following signature: [root@os-delivery ~]# cat /sys/kernel/debug/kmemleak unreferenced object 0xff3c1ca7252e6000 (size 8192): comm "kworker/0:0", pid 8, jiffies 4296833052 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<ffffffff991ec485>] __kmalloc_cache_noprof+0x275/0x340 [<ffffffffc0a6e06a>] ice_init_arfs+0x3a/0xe0 [ice] [<ffffffffc09f1027>] ice_vsi_cfg_def+0x607/0x850 [ice] [<ffffffffc09f244b>] ice_vsi_setup+0x5b/0x130 [ice] [<ffffffffc09c2131>] ice_init+0x1c1/0x460 [ice] [<ffffffffc09c64af>] ice_probe+0x2af/0x520 [ice] [<ffffffff994fbcd3>] local_pci_probe+0x43/0xa0 [<ffffffff98f07103>] work_for_cpu_fn+0x13/0x20 [<ffffffff98f0b6d9>] process_one_work+0x179/0x390 [<ffffffff98f0c1e9>] worker_thread+0x239/0x340 [<ffffffff98f14abc>] kthread+0xcc/0x100 [<ffffffff98e45a6d>] ret_from_fork+0x2d/0x50 [<ffffffff98e083ba>] ret_from_fork_asm+0x1a/0x30 ... It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21981? +

CVE-2025-21981 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-21981? +

CVE-2025-21981 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21981? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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