commit 46817cd44f6abe24e22d871758f512c3ca66c467
author Sean Klein <smklein@google.com> Sun Oct 15 18:25:26 2017 -0700
committer Sean Klein <smklein@google.com> Mon Oct 16 08:58:30 2017 -0700
tree 86a19a461f4b4322556f4336187dd39138f72742
parent 4fb0e81d7b7021f0aeefb86071834b2a0611b7d7

[exec] Avoid destroying launchpad structure when already freed by launchpad_go

ZX-1174 #done
ZX-1220 #done

Change-Id: Icba5f620923568d8a88aa20cb52c2f21f91aacea

src/os/exec_fuchsia_cgo.go

diff --git a/src/os/exec_fuchsia_cgo.go b/src/os/exec_fuchsia_cgo.go
index e10590d..25b446c 100644
--- a/src/os/exec_fuchsia_cgo.go
+++ b/src/os/exec_fuchsia_cgo.go
@@ -158,7 +158,11 @@
 	if status != zx.ErrOk {
 		return 0, errors.New("launchpad_create")
 	}
-	defer C.launchpad_destroy(lp)
+	defer func() {
+		if lp != nil {
+			C.launchpad_destroy(lp)
+		}
+	}()
 	status = zx.Status(C.launchpad_load_from_file(lp, nameC))
 	if status != zx.ErrOk {
 		return 0, errors.New("loading vdso")
@@ -193,6 +197,8 @@
 	}
 	h := C.zx_handle_t(0)
 	status = zx.Status(C.launchpad_go(lp, &h, nil))
+	// lp is freed by launchpad_go unconditionally
+	lp = nil
 	if status < 0 {
 		return 0, errors.New("launchpad error")
 	}