4 files changed, 14 insertions, 1 deletions
diff --git a/lib/esan/esan.cpp b/lib/esan/esan.cpp
index e7399e219..e6d6aff31 100644
--- a/lib/esan/esan.cpp
+++ b/lib/esan/esan.cpp
@@ -197,6 +197,9 @@ void initializeLibrary(ToolType Tool) {
   }
 
   initializeShadow();
+  if (__esan_which_tool == ESAN_WorkingSet)
+    initializeShadowWorkingSet();
+
   initializeInterceptors();
 
   if (__esan_which_tool == ESAN_CacheFrag) {
diff --git a/lib/esan/esan_interceptors.cpp b/lib/esan/esan_interceptors.cpp
index 5d4edb51d..7aefeb664 100644
--- a/lib/esan/esan_interceptors.cpp
+++ b/lib/esan/esan_interceptors.cpp
@@ -17,6 +17,7 @@
 #include "interception/interception.h"
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_linux.h"
 #include "sanitizer_common/sanitizer_stacktrace.h"
 
 using namespace __esan; // NOLINT
@@ -397,6 +398,11 @@ INTERCEPTOR(int, sigaction, int signum, const struct sigaction *act,
 // This is required to properly use internal_sigaction.
 namespace __sanitizer {
 int real_sigaction(int signum, const void *act, void *oldact) {
+  if (REAL(sigaction) == nullptr) {
+    // With an instrumented allocator, this is called during interceptor init
+    // and we need a raw syscall solution.
+    return internal_sigaction_syscall(signum, act, oldact);
+  }
   return REAL(sigaction)(signum, (const struct sigaction *)act,
                          (struct sigaction *)oldact);
 }
diff --git a/lib/esan/working_set.cpp b/lib/esan/working_set.cpp
index 9e7520f49..622fd29e8 100644
--- a/lib/esan/working_set.cpp
+++ b/lib/esan/working_set.cpp
@@ -182,10 +182,13 @@ static void takeSample(void *Arg) {
   }
 }
 
-void initializeWorkingSet() {
+// Initialization that must be done before any instrumented code is executed.
+void initializeShadowWorkingSet() {
   CHECK(getFlags()->cache_line_size == CacheLineSize);
   registerMemoryFaultHandler();
+}
 
+void initializeWorkingSet() {
   if (getFlags()->record_snapshots) {
     for (u32 i = 0; i < NumFreq; ++i)
       SizePerFreq[i].initialize(CircularBufferSizes[i]);
diff --git a/lib/esan/working_set.h b/lib/esan/working_set.h
index 3750a480a..034dfe6d9 100644
--- a/lib/esan/working_set.h
+++ b/lib/esan/working_set.h
@@ -21,6 +21,7 @@
 namespace __esan {
 
 void initializeWorkingSet();
+void initializeShadowWorkingSet();
 int finalizeWorkingSet();
 void processRangeAccessWorkingSet(uptr PC, uptr Addr, SIZE_T Size,
                                   bool IsWrite);