CVE-2025-21971

In the Linux kernel, the following vulnerability has been resolved: net_sched: Prevent creation of classes with TC_H_ROOT The function qdisc_tree_reduce_backlog() uses TC_H_ROOT as a termination condition when traversing up the qdisc tree to update parent backlog counters. However, if a class is created with classid TC_H_ROOT, the traversal terminates prematurely at this class instead of reaching the actual root qdisc, causing parent statistics to be incorrectly maintained. In case of DRR, this could lead to a crash as reported by Mingi Cho. Prevent the creation of any Qdisc class with classid TC_H_ROOT (0xFFFFFFFF) across all qdisc types, as suggested by Jamal.
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.25:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*

History

03 Nov 2025, 20:17

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CWE CWE-835
First Time Linux linux Kernel
Linux
References
  • () https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html -
  • () https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html -
References () https://git.kernel.org/stable/c/003d92c91cdb5a64b25a9a74cb8543aac9a8bb48 - () https://git.kernel.org/stable/c/003d92c91cdb5a64b25a9a74cb8543aac9a8bb48 - Patch
References () https://git.kernel.org/stable/c/0c3057a5a04d07120b3d0ec9c79568fceb9c921e - () https://git.kernel.org/stable/c/0c3057a5a04d07120b3d0ec9c79568fceb9c921e - Patch
References () https://git.kernel.org/stable/c/5c3ca9cb48b51bd72bf76b8b05e24f3cd53db5e7 - () https://git.kernel.org/stable/c/5c3ca9cb48b51bd72bf76b8b05e24f3cd53db5e7 - Patch
References () https://git.kernel.org/stable/c/78533c4a29ac3aeddce4b481770beaaa4f3bfb67 - () https://git.kernel.org/stable/c/78533c4a29ac3aeddce4b481770beaaa4f3bfb67 - Patch
References () https://git.kernel.org/stable/c/7a82fe67a9f4d7123d8e5ba8f0f0806c28695006 - () https://git.kernel.org/stable/c/7a82fe67a9f4d7123d8e5ba8f0f0806c28695006 - Patch
References () https://git.kernel.org/stable/c/94edfdfb9505ab608e86599d1d1e38c83816fc1c - () https://git.kernel.org/stable/c/94edfdfb9505ab608e86599d1d1e38c83816fc1c - Patch
References () https://git.kernel.org/stable/c/e05d9938b1b0ac40b6054cc5fa0ccbd9afd5ed4c - () https://git.kernel.org/stable/c/e05d9938b1b0ac40b6054cc5fa0ccbd9afd5ed4c - Patch
References () https://git.kernel.org/stable/c/e5ee00607bbfc97ef1526ea95b6b2458ac9e7cb7 - () https://git.kernel.org/stable/c/e5ee00607bbfc97ef1526ea95b6b2458ac9e7cb7 - Patch
CPE cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.25:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*

Information

Published : 2025-04-01 16:15

Updated : 2025-11-03 20:17


NVD link : CVE-2025-21971

Mitre link : CVE-2025-21971

CVE.ORG link : CVE-2025-21971


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')