Bug 2502552 (CVE-2026-64054)

Summary: CVE-2026-64054 kernel: net: shaper: reject duplicate leaves in GROUP request
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the `net/shaper` component of the Linux kernel. This vulnerability occurs because the `net_shaper_nl_group_doit()` function does not properly handle duplicate leaf entries in a GROUP request. A local attacker could exploit this by supplying the same leaf handle multiple times, leading to a double free of the parent pointer. This memory corruption can result in a denial of service or potentially lead to further compromise of the system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-07-19 17:05:43 UTC
In the Linux kernel, the following vulnerability has been resolved:

net: shaper: reject duplicate leaves in GROUP request

net_shaper_nl_group_doit() does not deduplicate NET_SHAPER_A_LEAVES
entries. When userspace supplies the same leaf handle twice, the same
old-parent pointer lands twice in old_nodes[]. The cleanup loop double
frees the parent. Of course the same parent may still be in old_nodes[]
twice if we are moving multiple of its leaves.

Note that this patch also implicitly fixes the fact that the
i >= leaves_count path forgets to set ret.