Merge pull request #72 from parca-dev/fix-oom

Safeguard read of sizetrace

Author: gnurizen

interpreter/luajit/offsets_test.go

@@ -229,7 +229,7 @@ func TestFiles(t *testing.T) {
 		require.NoError(t, err)
 
 		err = extractOffsets(ef, &ljd, interp)
-		require.NoError(t, err)
+		require.NoError(t, err, de)
 		require.NotZero(t, ljd.currentLOffset)
 		require.NotZero(t, ljd.g2Traces)
 		require.NotZero(t, ljd.g2Dispatch)

interpreter/luajit/trace.go

@@ -14,6 +14,7 @@ package luajit // import "go.opentelemetry.io/ebpf-profiler/interpreter/luajit"
 import (
 	"encoding/binary"
 	"errors"
+	"fmt"
 	"hash/fnv"
 
 	"go.opentelemetry.io/ebpf-profiler/libpf"
@@ -59,6 +60,9 @@ func getAndHashTraceAddrs(tracesAddr libpf.Address, rm remotememory.RemoteMemory
 	if err := rm.Read(tracesAddr, libpf.SliceFrom(&j)); err != nil {
 		return 0, 0, nil, err
 	}
+	if j.sizetrace > 65535 {
+		return 0, 0, nil, fmt.Errorf("invalid sizetrace %d (traces:%x)", j.sizetrace, tracesAddr)
+	}
 	traceAddrs = []libpf.Address{}
 	b := make([]byte, 8)
 	h := fnv.New64()