krb5 commit [krb5-1.15]: Fix krb5int_open_plugin_dirs() error handling

https://github.com/krb5/krb5/commit/ae9e99e9a3d41442128bdcb3b86fb3677db7c2d1
commit ae9e99e9a3d41442128bdcb3b86fb3677db7c2d1
Author: Martin Kittel <[email protected]>
Date:   Wed Mar 15 17:21:28 2017 +0100

    Fix krb5int_open_plugin_dirs() error handling
    
    In krb5int_open_plugin_dirs(), if constructing filepath fails,
    filepath is set to null but accessed a few lines later.  Add an error
    check before calling krb5int_open_plugin().
    
    (cherry picked from commit ec56309e95e37cb3c91bad2a696b9bd094620876)
    
    ticket: 8565
    version_fixed: 1.15.2

 src/util/support/plugins.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/util/support/plugins.c b/src/util/support/plugins.c
index b0bb2ad..47368be 100644
--- a/src/util/support/plugins.c
+++ b/src/util/support/plugins.c
@@ -592,9 +592,10 @@ krb5int_open_plugin_dirs (const char * const *dirnames,
                     }
                 }
 
-                if (krb5int_open_plugin (filepath, &handle, ep) == 0) {
+                if (!err && krb5int_open_plugin(filepath, &handle, ep) == 0) {
                     err = krb5int_plugin_file_handle_array_add (&h, &count, handle);
-                    if (!err) { handle = NULL; }  /* h takes ownership */
+                    if (!err)
+                        handle = NULL; /* h takes ownership */
                 }
 
                 free(filepath);