From: Arvin Schnell <aschnell@suse.de>
Date: Fri, 14 Sep 2018 10:16:11 +0000 (+0200)
Subject: - avoid setenv after fork (bsc#1107587)
X-Git-Tag: v0.6.0~4^2
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=1d47bcbee58dc8a5a220fe2aa207dea5d943dd12;p=thirdparty%2Fsnapper.git

- avoid setenv after fork (bsc#1107587)
---

diff --git a/package/snapper.changes b/package/snapper.changes
index 336c2e44..aaf41e4a 100644
--- a/package/snapper.changes
+++ b/package/snapper.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Fri Sep 14 12:13:05 CEST 2018 - aschnell@suse.com
+
+- avoid setenv after fork (bsc#1107587)
+
 -------------------------------------------------------------------
 Mon Jul 23 20:52:26 CEST 2018 - aschnell@suse.com
 
diff --git a/snapper/SystemCmd.cc b/snapper/SystemCmd.cc
index 83612bb9..22379479 100644
--- a/snapper/SystemCmd.cc
+++ b/snapper/SystemCmd.cc
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) [2004-2011] Novell, Inc.
+ * Copyright (c) 2018 SUSE LLC
  *
  * All Rights Reserved.
  *
@@ -30,6 +31,8 @@
 #include <string>
 #include <boost/algorithm/string.hpp>
 
+extern char **environ;
+
 #include "snapper/Log.h"
 #include "snapper/AppUtil.h"
 #include "snapper/SystemCmd.h"
@@ -205,11 +208,12 @@ SystemCmd::doExecute( const string& Cmd )
 		}
 	    }
 	y2deb("sout:" << pfds[0].fd << " serr:" << (Combine_b?-1:pfds[1].fd));
+
+	const vector<const char*> env = make_env();
+
 	switch( (Pid_i=fork()) )
 	    {
 	    case 0:
-		setenv( "LC_ALL", "C", 1 );
-		setenv( "LANGUAGE", "C", 1 );
 		if( dup2( sout[1], STDOUT_FILENO )<0 )
 		    {
 		    y2err("dup2 stdout child failed errno:" << errno << " (" << stringerror(errno) << ")");
@@ -231,8 +235,7 @@ SystemCmd::doExecute( const string& Cmd )
 		    y2err("close child failed errno:" << errno << " (" << stringerror(errno) << ")");
 		    }
 		closeOpenFds();
-		Ret_i = execl( Shell_Ci.c_str(), Shell_Ci.c_str(), "-c",
-			       Cmd.c_str(), NULL );
+		Ret_i = execle(Shell_Ci.c_str(), Shell_Ci.c_str(), "-c", Cmd.c_str(), nullptr, &env[0]);
 		y2err("SHOULD NOT HAPPEN \"" << Shell_Ci << "\" Ret:" << Ret_i);
 		break;
 	    case -1:
@@ -567,6 +570,27 @@ SystemCmd::logOutput() const
 }
 
 
+    vector<const char*>
+    SystemCmd::make_env() const
+    {
+	vector<const char*> env;
+
+	for (char** v = environ; *v != NULL; ++v)
+	{
+	    if (strncmp(*v, "LC_ALL=", strlen("LC_ALL=")) != 0 &&
+		strncmp(*v, "LANGUAGE=", strlen("LANGUAGE=")) != 0)
+		env.push_back(*v);
+	}
+
+	env.push_back("LC_ALL=C");
+	env.push_back("LANGUAGE=C");
+
+	env.push_back(nullptr);
+
+	return env;
+    }
+
+
 string
 SystemCmd::quote(const string& str)
 {
diff --git a/snapper/SystemCmd.h b/snapper/SystemCmd.h
index 0b812ff3..91bffb3f 100644
--- a/snapper/SystemCmd.h
+++ b/snapper/SystemCmd.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) [2004-2014] Novell, Inc.
+ * Copyright (c) 2018 SUSE LLC
  *
  * All Rights Reserved.
  *
@@ -101,6 +102,16 @@ namespace snapper
 
 	void logOutput() const;
 
+	/**
+	 * Constructs the environment for the child process.
+	 *
+	 * Must not be called after exec since allocating the memory
+	 * for the vector is not allowed then (in a multithreaded
+	 * program), see fork(2) and signal-safety(7). So simply call
+	 * it right before fork.
+	 */
+	vector<const char*> make_env() const;
+
 	FILE* File_aC[2];
 	std::vector<string> Lines_aC[2];
 	std::vector<string*> SelLines_aC[2];