1 files changed, 14 insertions, 8 deletions
diff --git a/src/runtime/cgocall.go b/src/runtime/cgocall.go
index a881ae1489..5f8ff8139a 100644
--- a/src/runtime/cgocall.go
+++ b/src/runtime/cgocall.go
@@ -406,24 +406,24 @@ var racecgosync uint64 // represents possible synchronization in C code
 
 // cgoCheckPointer checks if the argument contains a Go pointer that
 // points to a Go pointer, and panics if it does.
-func cgoCheckPointer(ptr interface{}, args ...interface{}) {
+func cgoCheckPointer(ptr interface{}, arg interface{}) {
 	if debug.cgocheck == 0 {
 		return
 	}
 
-	ep := (*eface)(unsafe.Pointer(&ptr))
+	ep := efaceOf(&ptr)
 	t := ep._type
 
 	top := true
-	if len(args) > 0 && (t.kind&kindMask == kindPtr || t.kind&kindMask == kindUnsafePointer) {
+	if arg != nil && (t.kind&kindMask == kindPtr || t.kind&kindMask == kindUnsafePointer) {
 		p := ep.data
 		if t.kind&kindDirectIface == 0 {
 			p = *(*unsafe.Pointer)(p)
 		}
-		if !cgoIsGoPointer(p) {
+		if p == nil || !cgoIsGoPointer(p) {
 			return
 		}
-		aep := (*eface)(unsafe.Pointer(&args[0]))
+		aep := efaceOf(&arg)
 		switch aep._type.kind & kindMask {
 		case kindBool:
 			if t.kind&kindMask == kindUnsafePointer {
@@ -460,7 +460,7 @@ const cgoResultFail = "cgo result has Go pointer"
 // depending on indir. The top parameter is whether we are at the top
 // level, where Go pointers are allowed.
 func cgoCheckArg(t *_type, p unsafe.Pointer, indir, top bool, msg string) {
-	if t.ptrdata == 0 {
+	if t.ptrdata == 0 || p == nil {
 		// If the type has no pointers there is nothing to do.
 		return
 	}
@@ -517,7 +517,7 @@ func cgoCheckArg(t *_type, p unsafe.Pointer, indir, top bool, msg string) {
 		st := (*slicetype)(unsafe.Pointer(t))
 		s := (*slice)(p)
 		p = s.array
-		if !cgoIsGoPointer(p) {
+		if p == nil || !cgoIsGoPointer(p) {
 			return
 		}
 		if !top {
@@ -548,11 +548,17 @@ func cgoCheckArg(t *_type, p unsafe.Pointer, indir, top bool, msg string) {
 			return
 		}
 		for _, f := range st.fields {
+			if f.typ.ptrdata == 0 {
+				continue
+			}
 			cgoCheckArg(f.typ, add(p, f.offset()), true, top, msg)
 		}
 	case kindPtr, kindUnsafePointer:
 		if indir {
 			p = *(*unsafe.Pointer)(p)
+			if p == nil {
+				return
+			}
 		}
 
 		if !cgoIsGoPointer(p) {
@@ -644,7 +650,7 @@ func cgoCheckResult(val interface{}) {
 		return
 	}
 
-	ep := (*eface)(unsafe.Pointer(&val))
+	ep := efaceOf(&val)
 	t := ep._type
 	cgoCheckArg(t, ep.data, t.kind&kindDirectIface == 0, false, cgoResultFail)
 }