Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix metadata_dst leak __bpf_redirect_neigh_v{4,6} Cilium has a BPF egress gateway feature which forces outgoing K8s Pod traffic to pass through dedicated egress gateways which then SNAT the traffic in order to interact with stable IPs outside the cluster. The traffic is directed to the gateway via vxlan tunnel in collect md mode. A recent BPF change utilized the bpf_redirect_neigh() helper to forward packets after the arrival and decap on vxlan, which turned out over time that the kmalloc-256 slab usage in kernel was ever-increasing. The issue was that vxlan allocates the metadata_dst object and attaches it through a fake dst entry to the skb. The latter was never released though given bpf_redirect_neigh() was merely setting the new dst entry via skb_dst_set() without dropping an existing one first.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
b4ab31414970a7a03a5d55d75083f2c101a30592 to < 3fba965a9aac0fa3cbd8138436a37af9ab466d79affectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < 057764172fcc6ee2ccb6c41351a55a9f054dc8fdaffectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < 2e67c2037382abb56497bb9d7b7e10be04eb5598affectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < b6bfe44b6dbb14a31d86c475cdc9c7689534fb09affectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < f36a305d30f557306d87c787ddffe094ac5dac89affectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < 7404ce888a45eb7da0508b7cbbe6f2e95302eeb8affectedb4ab31414970a7a03a5d55d75083f2c101a30592 to < 23f3770e1a53e6c7a553135011f547209e141e72affected
Linux Linux
Default version status: affected
5.10affected0 to < 5.10unaffected5.10.246 to ≤ 5.10.*unaffected5.15.195 to ≤ 5.15.*unaffected6.1.157 to ≤ 6.1.*unaffected6.6.113 to ≤ 6.6.*unaffected6.12.54 to ≤ 6.12.*unaffected6.17.4 to ≤ 6.17.*unaffected6.18 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/3fba965a9aac0fa3cbd8138436a37af9ab466d79 ↗
- https://git.kernel.org/stable/c/057764172fcc6ee2ccb6c41351a55a9f054dc8fd ↗
- https://git.kernel.org/stable/c/2e67c2037382abb56497bb9d7b7e10be04eb5598 ↗
- https://git.kernel.org/stable/c/b6bfe44b6dbb14a31d86c475cdc9c7689534fb09 ↗
- https://git.kernel.org/stable/c/f36a305d30f557306d87c787ddffe094ac5dac89 ↗
- https://git.kernel.org/stable/c/7404ce888a45eb7da0508b7cbbe6f2e95302eeb8 ↗
- https://git.kernel.org/stable/c/23f3770e1a53e6c7a553135011f547209e141e72 ↗