From ce9b512cccae86cb381ef6bcf8e554a364f88aa1 Mon Sep 17 00:00:00 2001 From: David Crawshaw Date: Tue, 17 Mar 2015 10:18:30 -0400 Subject: [PATCH] runtime: copy env strings on startup Some versions of libc, in this case Android's bionic, point environ directly at the envp memory. https://android.googlesource.com/platform/bionic/+/master/libc/bionic/libc_init_common.cpp#104 The Go runtime does something surprisingly similar, building the runtime's envs []string using gostringnocopy. Both libc and the Go runtime reusing memory interacts badly. When syscall.Setenv uses cgo to call setenv(3), C modifies the underlying memory of a Go string. This manifests on android/arm. With GOROOT=/data/local/tmp, a runtime test calls syscall.Setenv("/os"), resulting in runtime.GOROOT()=="/os\x00a/local/tmp/goroot". Avoid this by copying environment string memory into Go. Covered by runtime.TestFixedGOROOT on android/arm. Change-Id: Id0cf9553969f587addd462f2239dafca1cf371fa Reviewed-on: https://go-review.googlesource.com/7663 Reviewed-by: Keith Randall --- src/runtime/runtime1.go | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/runtime/runtime1.go b/src/runtime/runtime1.go index ae30adb2fc..21b9b1a2b6 100644 --- a/src/runtime/runtime1.go +++ b/src/runtime/runtime1.go @@ -80,7 +80,7 @@ func goenvs_unix() { envs = make([]string, n) for i := int32(0); i < n; i++ { - envs[i] = gostringnocopy(argv_index(argv, argc+1+i)) + envs[i] = gostring(argv_index(argv, argc+1+i)) } } -- 2.48.1