qemu/include/qapi
Michael Roth cee2dedb85 qapi: add visit_start_union and visit_end_union
In some cases an input visitor might bail out on filling out a
struct for various reasons, such as missing fields when running
in strict mode. In the case of a QAPI Union type, this may lead
to cases where the .kind field which encodes the union type
is uninitialized. Subsequently, other visitors, such as the
dealloc visitor, may use this .kind value as if it were
initialized, leading to assumptions about the union type which
in this case may lead to segfaults. For example, freeing an
integer value.

However, we can generally rely on the fact that the always-present
.data void * field that we generate for these union types will
always be NULL in cases where .kind is uninitialized (at least,
there shouldn't be a reason where we'd do this purposefully).

So pass this information on to Visitor implementation via these
optional start_union/end_union interfaces so this information
can be used to guard against the situation above. We will make
use of this information in a subsequent patch for the dealloc
visitor.

Cc: qemu-stable@nongnu.org
Reported-by: Fam Zheng <famz@redhat.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-09-26 13:14:10 -04:00
..
qmp qdict: Add qdict_join() 2014-05-19 11:36:48 +02:00
dealloc-visitor.h qapi: move include files to include/qobject/ 2012-12-19 08:31:31 +01:00
error.h error: error_is_set() is finally unused; remove 2014-05-21 11:57:58 +02:00
opts-visitor.h OptsVisitor: don't try to flatten overlong integer ranges 2013-08-20 11:52:00 -04:00
qmp-event.h qapi: add event helper functions 2014-06-23 11:01:25 -04:00
qmp-input-visitor.h qapi: move include files to include/qobject/ 2012-12-19 08:31:31 +01:00
qmp-output-visitor.h qapi: move include files to include/qobject/ 2012-12-19 08:31:31 +01:00
string-input-visitor.h qapi: move include files to include/qobject/ 2012-12-19 08:31:31 +01:00
string-output-visitor.h qapi: Add human mode to StringOutputVisitor 2014-02-14 21:12:03 +01:00
util.h rename parse_enum_option to qapi_enum_parse and make it public 2014-09-08 11:12:43 +01:00
visitor-impl.h qapi: add visit_start_union and visit_end_union 2014-09-26 13:14:10 -04:00
visitor.h qapi: add visit_start_union and visit_end_union 2014-09-26 13:14:10 -04:00