Add test for div by zero

include/svs/core/io/binary.h

@@ -53,6 +53,15 @@ get_dims(std::ifstream& stream, std::string_view source = {}, size_t elsize_hint
     size_t filesize = stream.tellg();
     stream.seekg(0, std::ifstream::beg);
 
+    if (header.num_vectors == 0 || header.vector_dim == 0) {
+        throw ANNEXCEPTION(
+            "Binary file {} has an invalid header (num_vectors={}, vector_dim={}).",
+            source.empty() ? "(unknown)"sv : source,
+            header.num_vectors,
+            header.vector_dim
+        );
+    }
+
     size_t filesize_minus_header = filesize - sizeof(header);
     size_t n_vec_elements =
         lib::narrow<size_t>(header.num_vectors) * lib::narrow<size_t>(header.vector_dim);

tests/svs/core/io/binary.cpp

@@ -29,6 +29,7 @@
 #include "catch2/matchers/catch_matchers_string.hpp"
 
 // stl
+#include <fstream>
 #include <iostream>
 #include <numeric>
 #include <vector>
@@ -133,4 +134,31 @@ CATCH_TEST_CASE("Testing Binary Reader Iterator", "[core][io]") {
             )
         );
     }
+
+    CATCH_SECTION("Malformed Header (zero dimensions)") {
+        // Crafted file with num_vectors == 0 and vector_dim == 0 must not trigger
+        // a divide-by-zero — the parser should reject it cleanly.
+        auto write_zero_header = [](const std::string& path) {
+            std::ofstream f(path, std::ios::binary | std::ios::trunc);
+            const uint32_t zero = 0;
+            f.write(reinterpret_cast<const char*>(&zero), sizeof(zero));
+            f.write(reinterpret_cast<const char*>(&zero), sizeof(zero));
+        };
+
+        std::string bad_file =
+            svs_test::prepare_temp_directory_v2() / "malformed_header.fbin";
+        write_zero_header(bad_file);
+
+        CATCH_REQUIRE_THROWS_MATCHES(
+            svs::io::binary::BinaryFile(bad_file).get_dims(),
+            svs::ANNException,
+            svs_test::ExceptionMatcher(Catch::Matchers::ContainsSubstring(bad_file))
+        );
+
+        CATCH_REQUIRE_THROWS_MATCHES(
+            svs::io::binary::BinaryReader<float>(bad_file),
+            svs::ANNException,
+            svs_test::ExceptionMatcher(Catch::Matchers::ContainsSubstring(bad_file))
+        );
+    }
 }