Fixes crashes when size_hint > UINT32_MAX is passed to H5Gcreate1

release_docs/RELEASE.txt

@@ -414,6 +414,22 @@ New Features
 
     Library:
     --------
+    - H5Gcreate1() now handles large size_hint parameters correctly
+
+      On 64-bit systems, large values of the size_t size_hint parameter
+      would be passed through a uint32_t struct field, causing a crash
+      on 64-bit Windows w/ MSVC and probably incorrect behavior or crashes
+      on other 64-bit systems.
+
+      The documentation for this API call was also incorrect, stating that
+      passing a negative value would cause the library to use a default
+      value. Instead, passing a "negative" value actually passes a very large
+      value, which is probably not what the user intends and can cause
+      crashes on 64-bit systems.
+
+        (DER - 2021/04/29, HDFFV-11241)
+
+
     - H5Pset_fapl_log() no longer crashes when passed an invalid fapl ID
 
       When passed an invalid fapl ID, H5Pset_fapl_log() would usually

src/H5Gdeprec.c

@@ -141,10 +141,9 @@ H5G_map_obj_type(H5O_type_t obj_type)
  *		specified NAME.  The group is opened for write access
  *		and it's object ID is returned.
  *
- *		The optional SIZE_HINT specifies how much file space to
- *		reserve to store the names that will appear in this
- *		group. If a non-positive value is supplied for the SIZE_HINT
- *		then a default size is chosen.
+ *		The SIZE_HINT parameter specifies how much file space to reserve
+ *		to store the names that will appear in this group. If zero is
+ *		supplied for the SIZE_HINT then a default size is chosen.
  *
  * Note:	Deprecated in favor of H5Gcreate2
  *
@@ -197,7 +196,7 @@ H5Gcreate1(hid_t loc_id, const char *name, size_t size_hint)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, H5I_INVALID_HID, "can't get group info")
 
         /* Set the non-default local heap size hint */
-        H5_CHECKED_ASSIGN(ginfo.lheap_size_hint, uint32_t, size_hint, size_t);
+        ginfo.lheap_size_hint = size_hint;
         if (H5P_set(gc_plist, H5G_CRT_GROUP_INFO_NAME, &ginfo) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, H5I_INVALID_HID, "can't set group info")
     }

src/H5Gpublic.h

@@ -569,8 +569,8 @@ typedef struct H5G_stat_t {
  *
  * \fgdta_loc_id
  * \param[in] name      Name of the group to create
- * \param[in] size_hint Optional parameter indicating the number of bytes
- *                      to reserve for the names that will appear in the group
+ * \param[in] size_hint The number of bytes to reserve for the names
+ *                      that will appear in the group
  *
  * \return \hid_t{group}
  *
@@ -592,11 +592,8 @@ typedef struct H5G_stat_t {
  *          group, is not limited.
  *
  *          \p size_hint is a hint for the number of bytes to reserve to store
- *          the names which will be eventually added to the new group. Passing a
- *          value of zero for \p size_hint is usually adequate since the library
- *          is able to dynamically resize the name heap, but a correct hint may
- *          result in better performance. If a non-positive value is supplied
- *          for \p size_hint, then a default size is chosen.
+ *          the names which will be eventually added to the new group. If this
+ *          parameter is zero, a default value will be used.
  *
  *          The return value is a group identifier for the open group. This
  *          group identifier should be closed by calling H5Gclose() when it is

src/H5Oprivate.h

@@ -684,7 +684,7 @@ typedef struct H5O_bogus_t {
  */
 typedef struct H5O_ginfo_t {
     /* "Old" format group info (not stored) */
-    uint32_t lheap_size_hint; /* Local heap size hint              */
+    size_t lheap_size_hint; /* Local heap size hint              */
 
     /* "New" format group info (stored) */
 

test/tmisc.c

@@ -4091,6 +4091,10 @@ test_misc23(void)
     tmp_id = H5Gcreate1(file_id, "/A/grp", (size_t)0);
     CHECK(tmp_id, FAIL, "H5Gcreate1");
 
+    /* Check that the largest size hint is acceptable */
+    tmp_id = H5Gcreate1(file_id, "/enormous_size_hint", SIZE_MAX);
+    CHECK(tmp_id, FAIL, "H5Gcreate1");
+
     status = H5Gclose(tmp_id);
     CHECK(status, FAIL, "H5Gclose");