krb5 commit [krb5-1.17]: Fix gss_set_sec_context_option() context creation

https://github.com/krb5/krb5/commit/3a1b4ba5d031a50a2217319ef0bfca055bcc10dc
commit 3a1b4ba5d031a50a2217319ef0bfca055bcc10dc
Author: Luke Howard <[email protected]>
Date:   Tue Nov 19 13:00:50 2019 -0500

    Fix gss_set_sec_context_option() context creation
    
    If gss_set_sec_context_option() creates a union context object, it
    must set the loopback pointer.
    
    [[email protected]: extracted this from a larger commit and wrote commit
    message]
    
    (cherry picked from commit 93b6d2a83849e157d7bec4f83fd94dbef10d6f05)
    
    ticket: 8850
    version_fixed: 1.17.1

 src/lib/gssapi/mechglue/g_set_context_option.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/src/lib/gssapi/mechglue/g_set_context_option.c b/src/lib/gssapi/mechglue/g_set_context_option.c
index 87db240..61f1147 100644
--- a/src/lib/gssapi/mechglue/g_set_context_option.c
+++ b/src/lib/gssapi/mechglue/g_set_context_option.c
@@ -97,6 +97,7 @@ gss_set_sec_context_option (OM_uint32 *minor_status,
 		return status;
 	    }
 
+	    ctx->loopback = ctx;
 	    ctx->internal_ctx_id = internal_ctx;
 	    *context_handle = (gss_ctx_id_t)ctx;
 	}