try to enable MSAN support with JIT

Author: addisoncrump

src/pcre2_jit_compile.c

@@ -43,6 +43,12 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "config.h"
 #endif
 
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#include <sanitizer/msan_interface.h>
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+
 #include "pcre2_internal.h"
 
 #ifdef SUPPORT_JIT
@@ -9721,7 +9727,7 @@ BACKTRACK_AS(recurse_backtrack)->matchingpath = LABEL();
 return cc + 1 + LINK_SIZE;
 }
 
-static sljit_s32 SLJIT_FUNC do_callout_jit(struct jit_arguments *arguments, pcre2_callout_block *callout_block, PCRE2_SPTR *jit_ovector)
+static sljit_s32 SLJIT_FUNC SLJIT_FUNC_ATTRIBUTE do_callout_jit(struct jit_arguments *arguments, pcre2_callout_block *callout_block, PCRE2_SPTR *jit_ovector)
 {
 PCRE2_SPTR begin;
 PCRE2_SIZE *ovector;

src/pcre2_jit_match.c

@@ -42,6 +42,12 @@ POSSIBILITY OF SUCH DAMAGE.
 #error This file must be included from pcre2_jit_compile.c.
 #endif
 
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#include <sanitizer/msan_interface.h>
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+
 #ifdef SUPPORT_JIT
 
 static SLJIT_NOINLINE int jit_machine_stack_exec(jit_arguments *arguments, jit_function executable_func)
@@ -178,6 +184,13 @@ match_data->rightchar = 0;
 match_data->mark = arguments.mark_ptr;
 match_data->matchedby = PCRE2_MATCHEDBY_JIT;
 
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+if (rc > 0)
+  __msan_unpoison(match_data->ovector, 2 * rc * sizeof(match_data->ovector[0]));
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+
 return match_data->rc;
 
 #endif  /* SUPPORT_JIT */

src/sljit/sljitConfigInternal.h

@@ -475,6 +475,19 @@ typedef double sljit_f64;
 #define SLJIT_FUNC
 #endif /* !SLJIT_FUNC */
 
+/* Disable instrumentation for these functions as they may not be sound */
+#ifndef SLJIT_FUNC_ATTRIBUTE
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#define SLJIT_FUNC_ATTRIBUTE __attribute__((no_sanitize("memory")))
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+#endif
+
+#ifndef SLJIT_FUNC_ATTRIBUTE
+#define SLJIT_FUNC_ATTRIBUTE
+#endif
+
 #ifndef SLJIT_INDIRECT_CALL
 #if ((defined SLJIT_CONFIG_PPC_64 && SLJIT_CONFIG_PPC_64) && (!defined _CALL_ELF || _CALL_ELF == 1)) \
 	|| ((defined SLJIT_CONFIG_PPC_32 && SLJIT_CONFIG_PPC_32) && defined _AIX)

src/sljit/sljitNativeX86_common.c

@@ -24,6 +24,12 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#include <sanitizer/msan_interface.h>
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+
 SLJIT_API_FUNC_ATTRIBUTE const char* sljit_get_platform_name(void)
 {
 	return "x86" SLJIT_CPUINFO;
@@ -476,6 +482,13 @@ static void execute_cpu_id(sljit_u32 info[4])
 	}
 
 #endif /* _MSC_VER && _MSC_VER >= 1400 */
+
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+__msan_unpoison(info, 4 * sizeof(sljit_u32));
+#endif /* __has_feature(memory_sanitizer) */
+#endif /* defined(__has_feature) */
+
 }
 
 static void get_cpu_features(void)