Compile libpcap with --disable-protochain #558
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There is a known issue that cloudfare/cbpfc can't properly handle "jump back" cBPF: cloudflare/cbpfc#36. Unfortunately, "protochain" pcap filter often generates such "jump back" instructions, leading to errors like: unable to compute blocks: instruction 18: ja 4294967281 flows past last instruction This patch disables protochain when compiling libpcap, so users receive a clearer error: $ pwru ip6 protochain 58 2025/05/23 22:42:53 Failed to inject filter ebpf for kprobe_multi_skb_5: failed to pcap_compile 'ip6 protochain 58': protochain not supported (l3=false) Signed-off-by: gray <[email protected]>
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There is a known issue that cloudfare/cbpfc can't properly handle "jump back" cBPF: cloudflare/cbpfc#37. Unfortunately, "protochain" pcap filter often generates such "jump back" instructions, leading to errors like:
This patch disables protochain when compiling libpcap, so users receive a clearer error:
Issue: #549