cryptui: Fix a crash with certification path (resend)

[André Hentschel]

see Juan Lang's comment on it.
---
 dlls/cryptui/main.c |    9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/dlls/cryptui/main.c b/dlls/cryptui/main.c
index a95a7a4..d92fbdd 100644
--- a/dlls/cryptui/main.c
+++ b/dlls/cryptui/main.c
@@ -4041,9 +4041,8 @@ static void show_cert_chain(HWND hwnd, struct hierarchy_data *data)
             tvis.u.item.pszText = name;
             tvis.u.item.state = TVIS_EXPANDED;
             tvis.u.item.stateMask = TVIS_EXPANDED;
-            if (i == 1 &&
-             (provSigner->pChainContext->TrustStatus.dwErrorStatus &
-             CERT_TRUST_IS_PARTIAL_CHAIN))
+            if (i == 1 && provSigner->pChainContext &&
+               (provSigner->pChainContext->TrustStatus.dwErrorStatus & CERT_TRUST_IS_PARTIAL_CHAIN))
             {
                 /* The root of the chain has a special case:  if the chain is
                  * a partial chain, the icon is a warning icon rather than an
@@ -4051,8 +4050,8 @@ static void show_cert_chain(HWND hwnd, struct hierarchy_data *data)
                  */
                 tvis.u.item.iImage = 2;
             }
-            else if (provSigner->pasCertChain[i - 1].pChainElement->TrustStatus.
-             dwErrorStatus == 0)
+            else if (i > 1 &&
+                     provSigner->pasCertChain[i - 1].pChainElement->TrustStatus.dwErrorStatus == 0)
                 tvis.u.item.iImage = 0;
             else
                 tvis.u.item.iImage = 1;
-- 

Best Regards, André Hentschel