krb5 commit: Fix gss_set_sec_context_option() context creation

[Greg Hudson]

https://github.com/krb5/krb5/commit/93b6d2a83849e157d7bec4f83fd94dbef10d6f05
commit 93b6d2a83849e157d7bec4f83fd94dbef10d6f05
Author: Luke Howard <lukeh at padl.com>
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.
    
    [ghudson at mit.edu: extracted this from a larger commit and wrote commit
    message]
    
    ticket: 8850 (new)
    tags: pullup
    target_version: 1.17-next
    target_version: 1.16-next

 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 8e25a27..c356131 100644
--- a/src/lib/gssapi/mechglue/g_set_context_option.c
+++ b/src/lib/gssapi/mechglue/g_set_context_option.c
@@ -96,6 +96,7 @@ 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;
 	}