bitbake: Remove custom exception backtrace formatting

Removes the code in bitbake to show custom backtrace formatting for
exceptions. In particular, the bitbake exception code prints function
arguments, which while helpful is a security problem when passwords and
other secrets can be passed as function arguments.

As it turns out, the handling of the custom serialized exception stack
frames was pretty much made obsolete by d7db75020ed ("event/msg: Pass
formatted exceptions"), which changed the events to pass a preformatted
stacktrack list of strings, but the passing of the serialized data was
never removed.

Change all the code to use the python traceback API to format exceptions
instead of the custom code; conveniently traceback.format_exception()
also returns a list of stack trace strings, so it can be used as a drop
in replacement for bb.exception.format_exception()

(Bitbake rev: c25e7ed128b9fd5b53d28d678238e2f3af52ef8b)

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

1 files changed, 24 insertions, 8 deletions

diff --git a/bitbake/lib/bb/cooker.py b/bitbake/lib/bb/cooker.py
index 6318ef4a8f..1cb3e189f4 100644
--- a/bitbake/lib/bb/cooker.py
+++ b/bitbake/lib/bb/cooker.py
@@ -17,7 +17,7 @@ import threading
 from io import StringIO, UnsupportedOperation
 from contextlib import closing
 from collections import defaultdict, namedtuple
-import bb, bb.exceptions, bb.command
+import bb, bb.command
 from bb import utils, data, parse, event, cache, providers, taskdata, runqueue, build
 import queue
 import signal
@@ -2097,7 +2097,6 @@ class Parser(multiprocessing.Process):
         except Exception as exc:
             tb = sys.exc_info()[2]
             exc.recipe = filename
-            exc.traceback = list(bb.exceptions.extract_traceback(tb, context=3))
             return True, None, exc
         # Need to turn BaseExceptions into Exceptions here so we gracefully shutdown
         # and for example a worker thread doesn't just exit on its own in response to
@@ -2298,8 +2297,12 @@ class CookerParser(object):
             return False
         except ParsingFailure as exc:
             self.error += 1
-            logger.error('Unable to parse %s: %s' %
-                     (exc.recipe, bb.exceptions.to_string(exc.realexception)))
+
+            exc_desc = str(exc)
+            if isinstance(exc, SystemExit) and not isinstance(exc.code, str):
+                exc_desc = 'Exited with "%d"' % exc.code
+
+            logger.error('Unable to parse %s: %s' % (exc.recipe, exc_desc))
             self.shutdown(clean=False)
             return False
         except bb.parse.ParseError as exc:
@@ -2308,20 +2311,33 @@ class CookerParser(object):
             self.shutdown(clean=False, eventmsg=str(exc))
             return False
         except bb.data_smart.ExpansionError as exc:
+            def skip_frames(f, fn_prefix):
+                while f and f.tb_frame.f_code.co_filename.startswith(fn_prefix):
+                    f = f.tb_next
+                return f
+
             self.error += 1
             bbdir = os.path.dirname(__file__) + os.sep
-            etype, value, _ = sys.exc_info()
-            tb = list(itertools.dropwhile(lambda e: e.filename.startswith(bbdir), exc.traceback))
+            etype, value, tb = sys.exc_info()
+
+            # Remove any frames where the code comes from bitbake. This
+            # prevents deep (and pretty useless) backtraces for expansion error
+            tb = skip_frames(tb, bbdir)
+            cur = tb
+            while cur:
+                cur.tb_next = skip_frames(cur.tb_next, bbdir)
+                cur = cur.tb_next
+
             logger.error('ExpansionError during parsing %s', value.recipe,
                          exc_info=(etype, value, tb))
             self.shutdown(clean=False)
             return False
         except Exception as exc:
             self.error += 1
-            etype, value, tb = sys.exc_info()
+            _, value, _ = sys.exc_info()
             if hasattr(value, "recipe"):
                 logger.error('Unable to parse %s' % value.recipe,
-                            exc_info=(etype, value, exc.traceback))
+                            exc_info=sys.exc_info())
             else:
                 # Most likely, an exception occurred during raising an exception
                 import traceback