krb5 commit [krb5-1.12]: Fix unlikely double free in PKINIT client code

[Tom Yu]

https://github.com/krb5/krb5/commit/68844329ad7d555e2c8dce9762b042f4b8f0ced1
commit 68844329ad7d555e2c8dce9762b042f4b8f0ced1
Author: Greg Hudson <ghudson at mit.edu>
Date:   Thu Mar 13 18:34:22 2014 -0400

    Fix unlikely double free in PKINIT client code
    
    In pa_pkinit_gen_req, if the cleanup handler is reached with non-zero
    retval and non-null out_data, out_data is freed, then dereferenced,
    then freed again.  This can only happen if one of the small fixed-size
    malloc requests fails after pkinit_as_req_create succeeds, so it is
    unlikely to occur in practice.
    
    (cherry picked from commit cc002d6c1ccfc08356d01ba83e72a46855d0302c)
    
    ticket: 7878
    version_fixed: 1.12.2
    status: resolved

 src/plugins/preauth/pkinit/pkinit_clnt.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/src/plugins/preauth/pkinit/pkinit_clnt.c b/src/plugins/preauth/pkinit/pkinit_clnt.c
index bfa25ae..cfef5b9 100644
--- a/src/plugins/preauth/pkinit/pkinit_clnt.c
+++ b/src/plugins/preauth/pkinit/pkinit_clnt.c
@@ -212,7 +212,6 @@ pa_pkinit_gen_req(krb5_context context,
 cleanup:
     if (der_req != NULL)
         krb5_free_data(context, der_req);
-    free(out_data);
 
     if (retval) {
         if (return_pa_data) {
@@ -222,9 +221,9 @@ cleanup:
         }
         if (out_data) {
             free(out_data->data);
-            free(out_data);
         }
     }
+    free(out_data);
     return retval;
 }