From b7e6c6c5451590f18df965a2a84550a63461d76e Mon Sep 17 00:00:00 2001

From: Robbie Harwood <rharwood@redhat.com>

Date: Mon, 27 Mar 2017 13:24:37 -0400

Subject: [PATCH] Prevent GSSError/_display_status() infinite recursion

I was unable to reproduce the problem, but this should prevent the issue.

Resolves: #111

---

 gssapi/raw/misc.pyx | 20 +++++++++++---------

 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/gssapi/raw/misc.pyx b/gssapi/raw/misc.pyx

index e278c4b..4ea0c55 100644

--- a/gssapi/raw/misc.pyx

+++ b/gssapi/raw/misc.pyx

@@ -139,7 +139,7 @@ def _display_status(unsigned int error_code, bint is_major_code,

             whether or not to call again for further messages

     Raises:

-       GSSError

+       ValueError

     """

     cdef int status_type

@@ -165,13 +165,16 @@ def _display_status(unsigned int error_code, bint is_major_code,

     if maj_stat == GSS_S_COMPLETE:

         call_again = bool(msg_ctx_out)

-

         msg_out = msg_buff.value[:msg_buff.length]

         gss_release_buffer(&min_stat, &msg_buff)

         return (msg_out, msg_ctx_out, call_again)

     else:

-        # NB(directxman12): this is highly unlikely to cause a recursive loop

-        raise GSSError(maj_stat, min_stat)

+        # This hides whatever error gss_display_status is complaining about,

+        # but obviates infinite recursion into stack exhaustion.  The

+        # exception raised here is handled by get_all_statuses(), which prints

+        # the code.

+        raise ValueError("gss_display_status call returned failure "

+                         "(major {0}, minor {1}).".format(maj_stat, min_stat))

 class GSSErrorRegistry(type):

@@ -294,8 +297,8 @@ class GSSError(Exception, metaclass=GSSErrorRegistry):

         try:

             msg, ctx, cont = _display_status(code, is_maj)

             res.append(msg.decode(msg_encoding))

-        except GSSError:

-            res.append(u'issue decoding code: {0}'.format(code))

+        except ValueError as e:

+            res.append(u'{0}  Decoding code: {1}'.format(e, code))

             cont = False

         while cont:

@@ -303,9 +306,8 @@ class GSSError(Exception, metaclass=GSSErrorRegistry):

                 msg, ctx, cont = _display_status(code, is_maj,

                                                  message_context=ctx)

                 res.append(msg.decode(msg_encoding))

-            except GSSError:

-                res.append(u'issue decoding '

-                           u'code: {0}'.format(code))

+            except ValueError:

+                res.append(u'{0}  Decoding code: {1}'.format(e, code))

                 cont = False

         return res

-- 

2.11.0