From 2700f7994e0645c11ab32bf9239ab6c215faec67 Mon Sep 17 00:00:00 2001
From: Nicky <none@none>
Date: Sun, 7 Feb 2016 23:47:58 +0100
Subject: [PATCH] FIRE-17517; LD_PRELOAD libcef.so when  launching a plugin
 that will dso-load media_plugin_cef. Reasoning is that libcef.so is bild with
 tcmalloc and thus will cause all kind of havok if not preloaded. Hopefully
 cefbuilds will stop doing this soon enough (see
 https://bitbucket.org/chromiumembedded/cef/issues/1827) and this can be
 reverted.

Alternative is to rebuild CEF each and every time for x86 and x64 when it is updated.

See also:
http://jira.phoenixviewer.com/browse/FIRE-17517
https://lists.secondlife.com/pipermail/opensource-dev/2015-July/010106.html
https://bitbucket.org/chromiumembedded/cef/issues/1827/tcmalloc-should-be-disabled-in-linux-osx
---
 indra/llcommon/llprocess.cpp             | 39 ++++++++++++++++++++++++
 indra/llcommon/llprocess.h               |  9 ++++++
 indra/llplugin/llpluginprocessparent.cpp |  8 +++++
 indra/newview/linux_tools/wrapper.sh     |  2 ++
 4 files changed, 58 insertions(+)

diff --git a/indra/llcommon/llprocess.cpp b/indra/llcommon/llprocess.cpp
index e0aa30cc1a..2815293a67 100755
--- a/indra/llcommon/llprocess.cpp
+++ b/indra/llcommon/llprocess.cpp
@@ -507,6 +507,40 @@ LLProcessPtr LLProcess::create(const LLSDOrParams& params)
 	}
 }
 
+// <FS:ND> Annoying preload hack to make tcmalloc in libcef.so play nicely.
+std::string installPreloadHack( std::string const &preload )
+{
+	std::string strOldPreload;
+#ifdef LL_LINUX
+	if( preload.size() )
+	{
+		std::string strPreload = preload;
+		if( getenv( "LD_PRELOAD" ) )
+		{
+			strOldPreload = getenv( "PRELOAD" );
+			strPreload = ":" + strOldPreload;
+		}
+
+		setenv( "LD_PRELOAD", strPreload.c_str(), 1 );
+	}
+#endif
+	return strOldPreload;
+}
+
+void uninstallPreloadHack( std::string const &preload, std::string const &strOldPreload )
+{
+#ifdef LL_LINUX
+	if( preload.empty() )
+		return;
+
+	if( strOldPreload.size() )
+		setenv( "LD_PRELOAD", strOldPreload.c_str(), 1 );
+	else
+		unsetenv( "LD_PRELOAD" );
+#endif	
+}
+// </FS:ND>
+
 /// Call an apr function returning apr_status_t. On failure, log warning and
 /// throw LLProcessError mentioning the function call that produced that
 /// result.
@@ -672,15 +706,20 @@ LLProcess::LLProcess(const LLSDOrParams& params):
 	// terminate with a null pointer
 	argv.push_back(NULL);
 
+	std::string strOldPreload = installPreloadHack( params.preload ); // FS:ND/> Install preload hack (if needed)
+	
 	// Launch! The NULL would be the environment block, if we were passing
 	// one. Hand-expand chkapr() macro so we can fill in the actual command
 	// string instead of the variable names.
 	if (ll_apr_warn_status(apr_proc_create(&mProcess, argv[0], &argv[0], NULL, procattr,
 										   gAPRPoolp)))
 	{
+		uninstallPreloadHack( params.preload, strOldPreload ); // <FS:ND/> Remove preload hack
 		throw LLProcessError(STRINGIZE(params << " failed"));
 	}
 
+	uninstallPreloadHack( params.preload, strOldPreload ); // <FS:ND/> Remove preload hack
+
 	// arrange to call status_callback()
 	apr_proc_other_child_register(&mProcess, &LLProcess::status_callback, this, mProcess.in,
 								  gAPRPoolp);
diff --git a/indra/llcommon/llprocess.h b/indra/llcommon/llprocess.h
index 43ccadc412..80d416bd01 100755
--- a/indra/llcommon/llprocess.h
+++ b/indra/llcommon/llprocess.h
@@ -227,6 +227,15 @@ public:
 		 * executable name.
 		 */
 		Optional<std::string> desc;
+
+		/**
+		   <FS:ND> HACK! libcef.so bleeds that intrusive tcmalloc hacks all over the process.
+		   This then causes awesome effects like crashes and memory corruption when the so is loaded dynamically.
+		   We uses this argument to force libcef.so be preloaded, which fixes this.
+		   The other solution would be to recompile CEF twice (x86/x64) for each CEF update. Which I really would like to avoid.
+		*/
+		Optional<std::string> preload;
+
 	};
 	typedef LLSDParamAdapter<Params> LLSDOrParams;
 
diff --git a/indra/llplugin/llpluginprocessparent.cpp b/indra/llplugin/llpluginprocessparent.cpp
index 6a69d5fda0..0ef5abef32 100755
--- a/indra/llplugin/llpluginprocessparent.cpp
+++ b/indra/llplugin/llpluginprocessparent.cpp
@@ -480,6 +480,14 @@ void LLPluginProcessParent::idle(void)
 				
 				    // Only argument to the launcher is the port number we're listening on
 				    mProcessParams.args.add(stringize(mBoundPort));
+#if LL_LINUX
+					if( mPluginFile.find( "cef" ) != std::string::npos && getenv( "FS_CEF_PRELOAD" ) )
+					{
+						mProcessParams.preload = getenv( "FS_CEF_PRELOAD" );
+						LL_INFOS( "Plugin" ) << "Forcing LD_PRELOAD for " << (std::string)mProcessParams.executable << " with a value of " << (std::string)mProcessParams.preload  << LL_ENDL;
+					}
+#endif
+					
 				    if (! (mProcess = LLProcess::create(mProcessParams)))
 				    {
 					    errorState();
diff --git a/indra/newview/linux_tools/wrapper.sh b/indra/newview/linux_tools/wrapper.sh
index 19cc99c7cc..df7fae834c 100755
--- a/indra/newview/linux_tools/wrapper.sh
+++ b/indra/newview/linux_tools/wrapper.sh
@@ -162,6 +162,8 @@ fi
 
 fi
 
+export FS_CEF_PRELOAD="`pwd`/lib/libcef.so"
+
 # Copy "$@" to ARGS array specifically to delete the --skip-gridargs switch.
 # The gridargs.dat file is no more, but we still want to avoid breaking
 # scripts that invoke this one with --skip-gridargs.