diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -10054,6 +10054,42 @@
 #define INIT___XUNAME
 #endif
 
+#if SANITIZER_INTERCEPT_FLOPEN
+#define FLOPEN_INTERCEPTOR_IMPL(flopen, path, flags, ...)                      \
+  {                                                                            \
+    void *ctx;                                                                 \
+    COMMON_INTERCEPTOR_ENTER(ctx, flopen, path, flags, ##__VA_ARGS__);         \
+    if (path) {                                                                \
+        COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);      \
+    }                                                                          \
+    return REAL(flopen)(path, flags, ##__VA_ARGS__);                           \
+  }
+
+#define FLOPENAT_INTERCEPTOR_IMPL(flopenat, dirfd, path, flags, ...)           \
+  {                                                                            \
+    void *ctx;                                                                 \
+    COMMON_INTERCEPTOR_ENTER(ctx, flopenat, dirfd, path, flags, ##__VA_ARGS__);\
+    if (path) {                                                                \
+        COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);      \
+    }                                                                          \
+    return REAL(flopenat)(dirfd, path, flags, ##__VA_ARGS__);                  \
+  }
+
+INTERCEPTOR(int, flopen, char *path, int flags) {
+  FLOPEN_INTERCEPTOR_IMPL(flopen, path, flags);
+}
+
+INTERCEPTOR(int, flopenat, int dirfd, char *path, int flags) {
+  FLOPENAT_INTERCEPTOR_IMPL(flopenat, dirfd, path, flags);
+}
+
+#define INIT_FLOPEN    \
+  COMMON_INTERCEPT_FUNCTION(flopen); \
+  COMMON_INTERCEPT_FUNCTION(flopenat);
+#else
+#define INIT_FLOPEN
+#endif
+
 #include "sanitizer_common_interceptors_netbsd_compat.inc"
 
 static void InitializeCommonInterceptors() {
@@ -10369,6 +10405,7 @@
   INIT_SIGALTSTACK;
   INIT_UNAME;
   INIT___XUNAME;
+  INIT_FLOPEN;
 
   INIT___PRINTF_CHK;
 }
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
@@ -651,7 +651,7 @@
 
 void FutexWake(atomic_uint32_t *p, u32 count) {
 #    if SANITIZER_FREEBSD
-  _umtx_op(p_, UMTX_OP_WAKE, count, 0, 0);
+  _umtx_op(p, UMTX_OP_WAKE, count, 0, 0);
 #    elif SANITIZER_NETBSD
                    /* No userspace futex-like synchronization */
 #    else
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
@@ -577,6 +577,7 @@
   (SI_POSIX && !(SANITIZER_MAC && SANITIZER_I386))
 #define SANITIZER_INTERCEPT_UNAME (SI_POSIX && !SI_FREEBSD)
 #define SANITIZER_INTERCEPT___XUNAME SI_FREEBSD
+#define SANITIZER_INTERCEPT_FLOPEN SI_FREEBSD
 
 // This macro gives a way for downstream users to override the above
 // interceptor macros irrespective of the platform they are on. They have
diff --git a/compiler-rt/test/sanitizer_common/TestCases/FreeBSD/flopen.cc b/compiler-rt/test/sanitizer_common/TestCases/FreeBSD/flopen.cc
new file mode 100644
--- /dev/null
+++ b/compiler-rt/test/sanitizer_common/TestCases/FreeBSD/flopen.cc
@@ -0,0 +1,20 @@
+// RUN: %clangxx -O0 -g %s -o %t -lutil && %run %t 2>&1 | FileCheck %s
+
+#include <sys/fcntl.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <libutil.h>
+
+int main(void) {
+  char buf[256];
+  arc4random_buf(buf, sizeof(buf));
+  int fd = flopen(nullptr, 0, 0);
+  assert(fd == -1);
+  fd = flopen("/TMP", O_RDONLY, 0600);
+  assert(fd == -1);
+  int dirfd = open("/tmp", O_CLOEXEC | O_DIRECTORY);
+  assert(dirfd != -1);
+  fd = flopenat(dirfd, buf, O_RDONLY, 0666);
+  assert(fd == -1);
+  return 0;
+}