CyberRota Analysis
AI-GeneratedThe vulnerability in the Linux kernel affects the net/sched component, specifically in the handling of nf_connlabels during error conditions in the tcf_ct_fill_params() function. This flaw allows an unprivileged user with CAP_NET_ADMIN access in a network namespace to leak nf_connlabels references, potentially leading to resource exhaustion as the count of used labels increases without being released. Organizations utilizing Linux kernel versions that include this component should prioritize patching to mitigate the risk of resource leaks and potential denial-of-service scenarios.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix nf_connlabels leak on two error paths tcf_ct_fill_params() calls nf_connlabels_get() (setting put_labels) when TCA_CT_LABELS is present, but two later error sites use a bare return instead of "goto err", skipping the err: nf_connlabels_put() cleanup. They also precede the "p->put_labels = put_labels" assignment, so the tcf_ct_params_free() fallback does not release the count either. Each failed RTM_NEWACTION on these paths leaks one nf_connlabels reference: net->ct.labels_used is incremented and never released. The action is reachable with CAP_NET_ADMIN over the netns, i.e. from an unprivileged user namespace on default-userns kernels. Impact: an unprivileged user with CAP_NET_ADMIN over a network namespace (e.g. via user namespaces) leaks one nf_connlabels reference per failed RTM_NEWACTION on the two error paths; net->ct.labels_used is never released. The err: label is safe to reach from both sites: p->tmpl is still NULL there (kzalloc'd, not yet assigned) and nf_ct_put(NULL) is a no-op, so no inline release is needed.