[asan] add address sanitizer support for syncd (sonic-net#1020)

add --enable-asan for syncd compilation
add SIGTERM handler that calls __lsan_do_leak_check() to generate a report

configure.ac

@@ -92,6 +92,26 @@ else
 	AM_CONDITIONAL(ARCH64, test `getconf LONG_BIT` = "64")
 fi
 
+AC_ARG_ENABLE(asan,
+[  --enable-asan      Compile with address sanitizer],
+[case "${enableval}" in
+	yes) asan_enabled=true ;;
+	no)  asan_enabled=false ;;
+	*) AC_MSG_ERROR(bad value ${enableval} for --enable-asan) ;;
+esac],[asan_enabled=false])
+
+if test "x$asan_enabled" = "xtrue"; then
+    CFLAGS_ASAN+=" -fsanitize=address"
+    CFLAGS_ASAN+=" -DASAN_ENABLED"
+    CFLAGS_ASAN+=" -ggdb -fno-omit-frame-pointer -U_FORTIFY_SOURCE"
+    AC_SUBST(CFLAGS_ASAN)
+
+    LDFLAGS_ASAN+=" -lasan"
+    AC_SUBST(LDFLAGS_ASAN)
+fi
+
+AM_CONDITIONAL(ASAN_ENABLED, test x$asan_enabled = xtrue)
+
 AC_PATH_PROGS(SWIG, [swig3.0 swig])
 
 CXXFLAGS_COMMON=""

debian/rules

@@ -67,9 +67,14 @@ binary-syncd-vs:
 #	dh_auto_configure -- \
 #	-DCMAKE_LIBRARY_PATH=$(DEB_HOST_MULTIARCH)
 
+configure_opts =
+ifeq ($(ENABLE_ASAN), y)
+	configure_opts += --enable-asan
+endif
+
 override_dh_auto_configure:
 	./autogen.sh
-	dh_auto_configure -- $(DEB_CONFIGURE_EXTRA_FLAGS) $(shell cat /tmp/syncd-build) ${SWSS_COMMON_CONFIG}
+	dh_auto_configure -- $(DEB_CONFIGURE_EXTRA_FLAGS) $(shell cat /tmp/syncd-build) ${SWSS_COMMON_CONFIG} $(configure_opts)
 
 override_dh_install:
 	dh_install

syncd/Asan.cpp

@@ -0,0 +1,25 @@
+#include "swss/logger.h"
+
+#include <csignal>
+#include <sanitizer/lsan_interface.h>
+
+static void sigterm_handler(int signo)
+{
+    SWSS_LOG_ENTER();
+
+    __lsan_do_leak_check();
+    signal(signo, SIG_DFL);
+    raise(signo);
+}
+
+__attribute__((constructor))
+static void asan_init()
+{
+    SWSS_LOG_ENTER();
+
+    if (signal(SIGTERM, sigterm_handler) == SIG_ERR)
+    {
+        SWSS_LOG_ERROR("failed to setup SIGTERM action");
+        exit(1);
+    }
+}

syncd/Makefile.am

@@ -56,11 +56,14 @@ libSyncd_a_CPPFLAGS = $(CODE_COVERAGE_CPPFLAGS)
 libSyncd_a_CXXFLAGS = $(DBGFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS_COMMON) $(CODE_COVERAGE_CXXFLAGS)
 
 syncd_SOURCES = main.cpp
+if ASAN_ENABLED
+syncd_SOURCES += Asan.cpp
+endif
 syncd_CPPFLAGS = $(CODE_COVERAGE_CPPFLAGS)
-syncd_CXXFLAGS = $(DBGFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS_COMMON) $(CODE_COVERAGE_CXXFLAGS)
+syncd_CXXFLAGS = $(DBGFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS_COMMON) $(CODE_COVERAGE_CXXFLAGS) $(CFLAGS_ASAN)
 syncd_LDADD = libSyncd.a $(top_srcdir)/lib/libSaiRedis.a -L$(top_srcdir)/meta/.libs -lsaimetadata -lsaimeta \
 			  -ldl -lhiredis -lswsscommon $(SAILIB) -lpthread -lzmq $(CODE_COVERAGE_LIBS)
-syncd_LDFLAGS = -rdynamic
+syncd_LDFLAGS = $(LDFLAGS_ASAN) -rdynamic
 
 if SAITHRIFT
 libSyncd_a_CXXFLAGS += -DSAITHRIFT=yes