Validate number of elements if in_sum is present

Author: EAddario

tools/imatrix/imatrix.cpp

@@ -940,11 +940,11 @@ bool IMatrixCollector::load_imatrix(const char * file_name) {
 
     for (const auto & sc : sums_counts_for) {
         const std::string &        name    = sc.first;
-        const struct ggml_tensor * in_sum   = std::get<2>(sc.second);
+        const struct ggml_tensor * in_sum  = std::get<2>(sc.second);
         const struct ggml_tensor * in_sum2 = std::get<0>(sc.second);
         const struct ggml_tensor * counts  = std::get<1>(sc.second);
 
-        if (!in_sum2 || !counts) {
+        if (!in_sum2 || !counts || (in_sum != nullptr && ggml_nelements(in_sum) != ggml_nelements(in_sum2))) {
             LOG_ERR("%s: mismatched sums and counts for %s\n", __func__, name.c_str());
             gguf_free(ctx_gguf);
             ggml_free(ctx);
@@ -981,16 +981,12 @@ bool IMatrixCollector::load_imatrix(const char * file_name) {
 
         // Recreate the state as expected by save_imatrix()
         for (int64_t j = 0; j < nval; j++) {
+            if (in_sum != nullptr) { e.activations[j] += ((const float *) in_sum->data)[j]; }
             e.values[j] += ((const float *) in_sum2->data)[j];
         }
         for (int64_t j = 0; j < ncounts; j++) {
             e.counts[j] += std::lround(((const float *) counts->data)[j]);
         }
-        if (in_sum != nullptr) {
-            for (int64_t j = 0; j < nval; j++) {
-                e.activations[j] += ((const float *) in_sum->data)[j];
-            }
-        }
     }
 
     // TODO: extract into its own method; this is also used by the legacy format