From 730bf2af85afbd5557adac5e3283f3ad59e90194 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Fri, 10 Apr 2015 18:46:27 -0400
Subject: [PATCH] Fix: add missing getenv wrapper

Required for old glibc.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 liblttng-ust/Makefile.am    |  3 ++-
 liblttng-ust/getenv.h       | 44 +++++++++++++++++++++++++++++++++++++
 liblttng-ust/lttng-clock.c  |  3 ++-
 liblttng-ust/lttng-getcpu.c |  3 ++-
 4 files changed, 50 insertions(+), 3 deletions(-)
 create mode 100644 liblttng-ust/getenv.h

diff --git a/liblttng-ust/Makefile.am b/liblttng-ust/Makefile.am
index bc71358f..78eac972 100644
--- a/liblttng-ust/Makefile.am
+++ b/liblttng-ust/Makefile.am
@@ -46,7 +46,8 @@ liblttng_ust_runtime_la_SOURCES = \
 	lttng-ust-uuid.h \
 	error.h \
 	tracef.c \
-	lttng-ust-tracef-provider.h
+	lttng-ust-tracef-provider.h \
+	getenv.h
 
 if HAVE_PERF_EVENT
 liblttng_ust_runtime_la_SOURCES += \
diff --git a/liblttng-ust/getenv.h b/liblttng-ust/getenv.h
new file mode 100644
index 00000000..05864fb8
--- /dev/null
+++ b/liblttng-ust/getenv.h
@@ -0,0 +1,44 @@
+#ifndef _COMPAT_GETENV_H
+#define _COMPAT_GETENV_H
+
+/*
+ * Copyright (C) 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <usterr-signal-safe.h>
+
+static inline
+int lttng_is_setuid_setgid(void)
+{
+	return geteuid() != getuid() || getegid() != getgid();
+}
+
+static inline
+char *lttng_secure_getenv(const char *name)
+{
+	if (lttng_is_setuid_setgid()) {
+		ERR("Getting environment variable '%s' from setuid/setgid binary refused for security reasons.",
+			name);
+		return NULL;
+	}
+	return getenv(name);
+}
+
+#endif /* _COMPAT_GETENV_H */
diff --git a/liblttng-ust/lttng-clock.c b/liblttng-ust/lttng-clock.c
index 557fc6b6..e8391e6d 100644
--- a/liblttng-ust/lttng-clock.c
+++ b/liblttng-ust/lttng-clock.c
@@ -26,6 +26,7 @@
 #include <urcu/arch.h>
 
 #include "clock.h"
+#include "getenv.h"
 
 struct lttng_trace_clock *lttng_trace_clock;
 
@@ -97,7 +98,7 @@ void lttng_ust_clock_init(void)
 	void (*libinit)(void);
 
 
-	libname = secure_getenv("LTTNG_UST_CLOCK_PLUGIN");
+	libname = lttng_secure_getenv("LTTNG_UST_CLOCK_PLUGIN");
 	if (!libname)
 		return;
 	handle = dlopen(libname, RTLD_NOW);
diff --git a/liblttng-ust/lttng-getcpu.c b/liblttng-ust/lttng-getcpu.c
index 8f4c0fe7..3e675a5a 100644
--- a/liblttng-ust/lttng-getcpu.c
+++ b/liblttng-ust/lttng-getcpu.c
@@ -25,6 +25,7 @@
 #include <urcu/system.h>
 #include <urcu/arch.h>
 
+#include "getenv.h"
 #include "../libringbuffer/getcpu.h"
 
 int (*lttng_get_cpu)(void);
@@ -41,7 +42,7 @@ void lttng_ust_getcpu_init(void)
 	void *handle;
 	void (*libinit)(void);
 
-	libname = secure_getenv("LTTNG_UST_GETCPU_PLUGIN");
+	libname = lttng_secure_getenv("LTTNG_UST_GETCPU_PLUGIN");
 	if (!libname)
 		return;
 	handle = dlopen(libname, RTLD_NOW);
-- 
2.34.1