fix(userspace/libsinsp): avoid possible UB when calling back or `fr…

…ont` without checking string emptiness. Signed-off-by: Federico Di Pierro <[email protected]>
falcosecurity · Sep 30, 2024 · bef6c42 · bef6c42
1 parent 8baec4b
commit bef6c42
Show file tree

Hide file tree

Showing 3 changed files with 3 additions and 3 deletions.
diff --git a/userspace/libsinsp/parsers.cpp b/userspace/libsinsp/parsers.cpp
@@ -2384,7 +2384,7 @@ std::string sinsp_parser::parse_dirfd(sinsp_evt *evt, std::string_view name, int
 		return "<UNKNOWN>";
 	}
 
-	if(fdinfo->m_name.back() == '/') {
+	if(!fdinfo->m_name.empty() && fdinfo->m_name.back() == '/') {
 		return fdinfo->m_name;
 	}
 	return fdinfo->m_name + '/';

diff --git a/userspace/libsinsp/sinsp_filtercheck_fdlist.cpp b/userspace/libsinsp/sinsp_filtercheck_fdlist.cpp
@@ -233,7 +233,7 @@ uint8_t *sinsp_filter_check_fdlist::extract_single(sinsp_evt *evt,
 		pos += 10;
 	}
 
-	if(m_strval.size() != 0) {
+	if(!m_strval.empty()) {
 		if(m_strval.back() == ',') {
 			m_strval = m_strval.substr(0, m_strval.size() - 1);
 		}

diff --git a/userspace/libsinsp/sinsp_filtercheck_fspath.cpp b/userspace/libsinsp/sinsp_filtercheck_fspath.cpp
@@ -291,7 +291,7 @@ static inline std::string format_dirfd(sinsp_evt* evt) {
 		return "<UNKNOWN>";
 	}
 
-	if(fd_info_dirfd->m_name.back() == '/') {
+	if(!fd_info_dirfd->m_name.empty() && fd_info_dirfd->m_name.back() == '/') {
 		return fd_info_dirfd->m_name;
 	}