kprobe log fix

backend/src/utilities/ebpf_bridge_events.py

@@ -8,6 +8,7 @@ import ctypes as ct
 import hashlib
 import ipaddress
 import json
+import os
 import signal
 import socket
 import sys
@@ -395,13 +396,41 @@ def _emit_event(cpu: int, data: int, size: int) -> None:
 
 
 def _attach_kprobe_first(bpf: BPF, symbols: list[str], fn_name: str) -> str:
-    for symbol in symbols:
+    supported = _supported_kprobe_symbols(symbols)
+    if not supported:
+        raise RuntimeError(f"No supported kprobe symbols found for {fn_name}: {symbols}")
+
+    for symbol in supported:
         try:
             bpf.attach_kprobe(event=symbol, fn_name=fn_name)
             return symbol
         except Exception:
             continue
-    raise RuntimeError(f"Failed to attach {fn_name} to any of {symbols}")
+    raise RuntimeError(f"Failed to attach {fn_name} to any of {supported}")
+
+
+def _supported_kprobe_symbols(symbols: list[str]) -> list[str]:
+    try:
+        available = set()
+        for symbol in symbols:
+            for candidate in BPF.get_kprobe_functions(symbol.encode()):
+                decoded = candidate.decode("utf-8", "replace")
+                if decoded == symbol:
+                    available.add(symbol)
+        if available:
+            return [symbol for symbol in symbols if symbol in available]
+    except Exception:
+        pass
+
+    if os.path.exists("/proc/kallsyms"):
+        try:
+            with open("/proc/kallsyms", "r", encoding="utf-8", errors="replace") as handle:
+                names = {line.rsplit(" ", 1)[-1].strip() for line in handle}
+            return [symbol for symbol in symbols if symbol in names]
+        except Exception:
+            pass
+
+    return symbols
 
 
 def _attach_egress_probe(bpf: BPF) -> str: