Msan: Unpoison getrandom() syscall result

nikic · nikic · commit 7e6db7006468 · 2019-07-01T11:14:17.000+02:00
diff --git a/ext/standard/random.c b/ext/standard/random.c
@@ -38,6 +38,10 @@
 # endif
 #endif
 
+#if __has_feature(memory_sanitizer)
+# include <sanitizer/msan_interface.h>
+#endif
+
 #ifdef ZTS
 int random_globals_id;
 #else
@@ -133,6 +137,10 @@ PHPAPI int php_random_bytes(void *bytes, size_t size, zend_bool should_throw)
 			}
 		}
 
+#if __has_feature(memory_sanitizer)
+		/* MSan does not instrument manual syscall invocations. */
+		__msan_unpoison(bytes + read_bytes, n);
+#endif
 		read_bytes += (size_t) n;
 	}
 #endif

Original file line number	Diff line number	Diff line change
`@@ -38,6 +38,10 @@`
`38`	`38`	`# endif`
`39`	`39`	`#endif`
`40`	`40`
	`41`	`+#if __has_feature(memory_sanitizer)`
	`42`	`+# include <sanitizer/msan_interface.h>`
	`43`	`+#endif`
	`44`	`+`
`41`	`45`	`#ifdef ZTS`
`42`	`46`	`int random_globals_id;`
`43`	`47`	`#else`
`@@ -133,6 +137,10 @@ PHPAPI int php_random_bytes(void *bytes, size_t size, zend_bool should_throw)`
`133`	`137`	`}`
`134`	`138`	`}`
`135`	`139`
	`140`	`+#if __has_feature(memory_sanitizer)`
	`141`	`+ /* MSan does not instrument manual syscall invocations. */`
	`142`	`+ __msan_unpoison(bytes + read_bytes, n);`
	`143`	`+#endif`
`136`	`144`	`read_bytes += (size_t) n;`
`137`	`145`	`}`
`138`	`146`	`#endif`