Merge pull request #27865 from MaximSmolskiy:fix_invalid_memory_access_in_usac

Fix invalid memory access in USAC #27865

### Pull Request Readiness Checklist

Fix #27863 

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

modules/calib3d/src/usac/fundamental_solver.cpp

@@ -385,7 +385,7 @@ public:
             Matx<double, 9, 9> AtA_(AtA), U, Vt;
             Vec<double, 9> W;
             SVD::compute(AtA_, W, U, Vt, SVD::FULL_UV + SVD::MODIFY_A);
-            models = std::vector<Mat> { Mat_<double>(3, 3, Vt.val + 72 /*=8*9*/) };
+            models = std::vector<Mat> { Mat_<double>(3, 3, Vt.val + 72 /*=8*9*/).clone() };
 #endif
         }
 
@@ -503,7 +503,7 @@ public:
        Matx<double, 9, 9> AtA_(covariance), U, Vt;
        Vec<double, 9> W;
        SVD::compute(AtA_, W, U, Vt, SVD::FULL_UV + SVD::MODIFY_A);
-       models = std::vector<Mat> { Mat_<double>(3, 3, Vt.val + 72 /*=8*9*/) };
+       models = std::vector<Mat> { Mat_<double>(3, 3, Vt.val + 72 /*=8*9*/).clone() };
 #endif
         if (enforce_rank)
             FundamentalDegeneracy::recoverRank(models[0], is_fundamental);

modules/calib3d/src/usac/homography_solver.cpp

@@ -253,7 +253,7 @@ public:
             Matx<double, 9, 9> Vt;
             Vec<double, 9> D;
             if (! eigen(Matx<double, 9, 9>(AtA), D, Vt)) return 0;
-            H = Mat_<double>(3, 3, Vt.val + 72/*=8*9*/);
+            H = Mat_<double>(3, 3, Vt.val + 72/*=8*9*/).clone();
 #endif
         }
         const auto * const h = (double *) H.data;