From: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date: Sun, 25 Mar 2018 20:26:13 +0000 (+0200)
Subject: fuzz-unit-file: add __has_feature(memory_sanitizer) when skipping ListenNetlink=
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=7c9bebfd22b33d026e66227d9b3a2b33d4a3265b;p=elogind.git

fuzz-unit-file: add __has_feature(memory_sanitizer) when skipping ListenNetlink=

https://clang.llvm.org/docs/MemorySanitizer.html#id5 documents this
check as the way to detect MemorySanitizer at compilation time. We
only need to skip the test if MemorySanitizer is used.

Also, use this condition in cg_slice_to_path(). There, the code that is
conditionalized is not harmful in any way (it's just unnecessary), so remove
the FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION condition.

Fixes #8482.
---

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index dbc2938c0..11d979529 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -2086,7 +2086,7 @@ int cg_slice_to_path(const char *unit, char **ret) {
                 _cleanup_free_ char *escaped = NULL;
                 char n[dash - p + sizeof(".slice")];
 
-#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+#if HAS_FEATURE_MEMORY_SANITIZER
                 /* msan doesn't instrument stpncpy, so it thinks
                  * n is later used unitialized:
                  * https://github.com/google/sanitizers/issues/926
diff --git a/src/basic/macro.h b/src/basic/macro.h
index 3a6fc6f58..8e61ff068 100644
--- a/src/basic/macro.h
+++ b/src/basic/macro.h
@@ -63,6 +63,17 @@
 #endif
 #endif
 
+#if !defined(HAS_FEATURE_MEMORY_SANITIZER)
+#  if defined(__has_feature)
+#    if __has_feature(memory_sanitizer)
+#      define HAS_FEATURE_MEMORY_SANITIZER 1
+#    endif
+#  endif
+#  if !defined(HAS_FEATURE_MEMORY_SANITIZER)
+#    define HAS_FEATURE_MEMORY_SANITIZER 0
+#  endif
+#endif
+
 /* Temporarily disable some warnings */
 #define DISABLE_WARNING_DECLARATION_AFTER_STATEMENT                     \
         _Pragma("GCC diagnostic push");                                 \
@@ -427,7 +438,6 @@ static inline unsigned long ALIGN_POWER2(unsigned long u) {
         static inline void func##p(type *p) {                   \
                 if (*p)                                         \
                         func(*p);                               \
-        }                                                       \
-        struct __useless_struct_to_allow_trailing_semicolon__
+        }
 
 #include "log.h"