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.
Metrics
Affected Vendors & Products
References
History
Mon, 03 Nov 2025 20:30:00 +0000
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| References |
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Fri, 31 Oct 2025 19:30:00 +0000
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| First Time appeared |
Linux
Linux linux Kernel |
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| Weaknesses | CWE-835 | |
| CPEs | 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:*:*:*:*:*:* |
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| Vendors & Products |
Linux
Linux linux Kernel |
Fri, 23 May 2025 02:45:00 +0000
| Type | Values Removed | Values Added |
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| Weaknesses | CWE-703 |
Thu, 10 Apr 2025 13:15:00 +0000
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| References |
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Wed, 02 Apr 2025 14:00:00 +0000
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| Metrics |
threat_severity
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cvssV3_1
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Tue, 01 Apr 2025 16:00:00 +0000
| Type | Values Removed | Values Added |
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| Description | 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. | |
| Title | net_sched: Prevent creation of classes with TC_H_ROOT | |
| References |
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Status: PUBLISHED
Assigner: Linux
Published: 2025-04-01T15:47:04.448Z
Updated: 2025-11-03T19:40:14.063Z
Reserved: 2024-12-29T08:45:45.797Z
Link: CVE-2025-21971
No data.
Status : Modified
Published: 2025-04-01T16:15:28.440
Modified: 2025-11-03T20:17:33.693
Link: CVE-2025-21971