Merge pull request #1564 from NetCDF-World-Domination-Council/ejh_docs_cleanup

fix memory issue that may occur for some HDF5 file opens

Author: WardF

libhdf5/hdf5open.c

@@ -2532,6 +2532,10 @@ rec_read_metadata(NC_GRP_INFO_T *grp)
     /* Get HDF5-specific group info. */
     hdf5_grp = (NC_HDF5_GRP_INFO_T *)grp->format_grp_info;
 
+    /* Set user data for iteration over any child groups. */
+    udata.grp = grp;
+    udata.grps = nclistnew();
+
     /* Open this HDF5 group and retain its grpid. It will remain open
      * with HDF5 until this file is nc_closed. */
     if (!hdf5_grp->hdf_grpid)
@@ -2579,10 +2583,6 @@ rec_read_metadata(NC_GRP_INFO_T *grp)
         iter_index = H5_INDEX_NAME;
     }
 
-    /* Set user data for iteration over any child groups. */
-    udata.grp = grp;
-    udata.grps = nclistnew();
-
     /* Iterate over links in this group, building lists for the types,
      * datasets and groups encountered. A pointer to udata will be
      * passed as a parameter to the callback function

nc_test4/tst_interops5.c

@@ -1,8 +1,10 @@
-/* This is part of the netCDF package. Copyright 2005-2018, University
-   Corporation for Atmospheric Research/Unidata.  See COPYRIGHT file
+/* This is part of the netCDF package. Copyright 2005-2019, University
+   Corporation for Atmospheric Research/Unidata. See COPYRIGHT file
    for conditions of use.
 
    Test that HDF5 and NetCDF-4 can read and write the same file.
+
+   Ed Hartnett
 */
 #include <config.h>
 #include <nc_tests.h>
@@ -253,5 +255,24 @@ main(int argc, char **argv)
    }
    SUMMARIZE_ERR;
 #endif /* USE_SZIP */
+   /* This test suggested by user brentd42 to find a memory problem in
+    * function rec_read_metadata(). This test demonstrates the bug on
+    * address sanitizer runs. See
+    * https://github.com/Unidata/netcdf-c/issues/1558. */
+   printf("*** testing error when opening HDF5 file without creating ordering...");
+   {
+       hid_t file_hid;
+       int ncid;
+       char *filename = "tst_interops5.h5";
+
+       /* Create a HDF5 file, but don't set creation ordering on. */
+       file_hid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+       H5Fclose(file_hid);
+
+       /* Open the file with netCDF. */
+       nc_set_log_level(3);
+       if (nc_open(filename, NC_WRITE, &ncid) != NC_ECANTWRITE) ERR;
+   }
+   SUMMARIZE_ERR;
    FINAL_RESULTS;
 }