Merge pull request #1053 in HDFFV/hdf5 from ~LRKNOX/hdf5_lrk:hdf5_1_8 to hdf5_1_8

* commit '878537c9cb639e84ae67c65729620cee541c253b':
  Added a "won't fix" RELEASE.txt entry for HDFFV-10356.
  Fix for HDFFV-10357 (CVE-2017-17508).

2 files changed, 40 insertions, 0 deletions

diff --git a/release_docs/RELEASE.txt b/release_docs/RELEASE.txt
index ebdb5f8..30b148a 100644
--- a/release_docs/RELEASE.txt
+++ b/release_docs/RELEASE.txt
@@ -174,6 +174,41 @@ Bug Fixes since HDF5-1.8.20
 
       (DER - 2018/02/26, HDFFV-10355)
 
+    - If an HDF5 file contains a malformed compound datatype with a
+      suitably large offset, the type conversion code can run off
+      the end of the type conversion buffer, causing a segmentation
+      fault.
+
+      This issue was reported to The HDF Group as issue #CVE-2017-17507.
+
+      NOTE: The HDF5 C library cannot produce such a file. This condition
+            should only occur in a corrupt (or deliberately altered) file
+            or a file created by third-party software.
+
+      THE HDF GROUP WILL NOT FIX THIS BUG AT THIS TIME
+
+      Fixing this problem would involve updating the publicly visible
+      H5T_conv_t function pointer typedef and versioning the API calls
+      which use it. We normally only modify the public API during
+      major releases, so this bug will not be fixed at this time.
+
+      (DER - 2018/02/26, HDFFV-10356)
+
+    - If an HDF5 file contains a malformed compound type which contains
+      a member of size zero, a division by zero error will occur while
+      processing the type.
+
+      This issue was reported to The HDF Group as issue #CVE-2017-17508.
+
+      NOTE: The HDF5 C library cannot produce such a file. This condition
+            should only occur in a corrupt (or deliberately altered) file
+            or a file created by third-party software.
+
+      Checking for zero before dividing fixes the problem. Instead of the
+      division by zero, the normal HDF5 error handling is invoked.
+
+      (DER - 2018/02/26, HDFFV-10357)
+
     Configuration
     -------------
     - CMake
diff --git a/src/H5T.c b/src/H5T.c
index 36b4c63..f4c10a5 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -5174,6 +5174,11 @@ H5T_set_loc(H5T_t *dt, H5F_t *f, H5T_loc_t loc)
 
                             /* Check if the field changed size */
                             if(old_size != memb_type->shared->size) {
+
+                                /* Fail if the old_size is zero */
+                                if (0 == old_size)
+                                    HGOTO_ERROR(H5E_DATATYPE, H5E_BADVALUE, FAIL, "old_size of zero would cause division by zero");
+
                                 /* Adjust the size of the member */
                                 dt->shared->u.compnd.memb[i].size = (dt->shared->u.compnd.memb[i].size*memb_type->shared->size)/old_size;