libndr: change subcontext buffer allocation to allocate on subcontext_start.

Guenther
(cherry picked from commit c9fa97b01774d767acfabaf1eec7a6aad1510440)

diff --git a/librpc/ndr/ndr.c b/librpc/ndr/ndr.c
index 17eb5e5a0586217ffde4cb00d7419e37805a9a01..521d4ec8d2516a7b1e634add45d63272e73002ab 100644 (file)
--- a/librpc/ndr/ndr.c
+++ b/librpc/ndr/ndr.c
@@ -572,6 +572,11 @@ _PUBLIC_ enum ndr_err_code ndr_push_subcontext_start(struct ndr_push *ndr,
        NDR_ERR_HAVE_NO_MEMORY(subndr);
        subndr->flags   = ndr->flags;
 
+       if (size_is > 0) {
+               NDR_CHECK(ndr_push_zero(subndr, size_is));
+               subndr->offset = 0;
+       }
+
        *_subndr = subndr;
        return NDR_ERR_SUCCESS;
 }
@@ -588,12 +593,11 @@ _PUBLIC_ enum ndr_err_code ndr_push_subcontext_end(struct ndr_push *ndr,
 
        if (size_is >= 0) {
                padding_len = size_is - subndr->offset;
-               if (padding_len > 0) {
-                       NDR_CHECK(ndr_push_zero(subndr, padding_len));
-               } else if (padding_len < 0) {
+               if (padding_len < 0) {
                        return ndr_push_error(ndr, NDR_ERR_SUBCONTEXT, "Bad subcontext (PUSH) content_size %d is larger than size_is(%d)",
                                              (int)subndr->offset, (int)size_is);
                }
+               subndr->offset = size_is;
        }
 
        switch (header_size) {