executor, syz-fuzzer: fix readonly root

2 files changed, 15 insertions, 5 deletions

diff --git a/executor/cov_filter.h b/executor/cov_filter.h
index a8b6624fe..8c7531d1f 100644
--- a/executor/cov_filter.h
+++ b/executor/cov_filter.h
@@ -14,13 +14,13 @@ struct cov_filter_t {
 
 static cov_filter_t* cov_filter;
 
-static void init_coverage_filter()
+static void init_coverage_filter(char* filename)
 {
-	int f = open("/syz-cover-bitmap", O_RDONLY);
+	int f = open(filename, O_RDONLY);
 	if (f < 0) {
 		// We don't fail here because we don't know yet if we should use coverage filter or not.
 		// We will receive the flag only in execute flags and will fail in coverage_filter if necessary.
-		debug("bitmap is no found, coverage filter disabled\n");
+		debug("bitmap is not found, coverage filter disabled\n");
 		return;
 	}
 	struct stat st;
@@ -55,7 +55,7 @@ static bool coverage_filter(uint64 pc)
 }
 
 #else
-static void init_coverage_filter()
+static void init_coverage_filter(char* filename)
 {
 }
 #endif
diff --git a/executor/executor.cc b/executor/executor.cc
index 35123b32d..161616be4 100644
--- a/executor/executor.cc
+++ b/executor/executor.cc
@@ -444,7 +444,17 @@ int main(int argc, char** argv)
 			// Don't enable comps because we don't use them in the fuzzer yet.
 			cover_enable(&extra_cov, false, true);
 		}
-		init_coverage_filter();
+		char sep = '/';
+#if GOOS_windows
+		sep = '\\';
+#endif
+		char filename[1024] = {0};
+		char* end = strrchr(argv[0], sep);
+		size_t len = end - argv[0];
+		strncpy(filename, argv[0], len + 1);
+		strncat(filename, "syz-cover-bitmap", 17);
+		filename[sizeof(filename) - 1] = '\0';
+		init_coverage_filter(filename);
 	}
 
 	int status = 0;