hardening: enable address sanitizer build

This adds --{disable,enable}-asan. It is disabled by default.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

configure.ac

@@ -428,6 +428,12 @@ AC_ARG_ENABLE([commands],
 	[], [enable_commands=yes])
 AM_CONDITIONAL([ENABLE_COMMANDS], [test "x$enable_commands" = "xyes"])
 
+# Build with ASAN commands
+AC_ARG_ENABLE([asan],
+	[AC_HELP_STRING([--enable-asan], [build with address sanitizer enabled [default=no]])],
+	[], [enable_asan=no])
+AM_CONDITIONAL([ENABLE_ASAN], [test "x$enable_asan" = "xyes"])
+
 # Optional test binaries
 AC_ARG_ENABLE([tests],
 	[AC_HELP_STRING([--enable-tests], [build test/example binaries [default=no]])],
@@ -1001,6 +1007,7 @@ Documentation:
 
 Debugging:
  - tests: $enable_tests
+ - ASAN: $enable_asan
  - mutex debugging: $enable_mutex_debugging
 
 Paths:

src/lxc/Makefile.am

@@ -235,6 +235,10 @@ liblxc_la_CFLAGS = -fPIC \
 		   -DPIC \
 		   $(AM_CFLAGS) \
 		   -pthread
+if ENABLE_ASAN
+liblxc_la_CFLAGS += -fsanitize=address \
+		    -fno-omit-frame-pointer
+endif
 
 liblxc_la_LDFLAGS = -pthread \
 		    -Wl,-no-undefined \