From: Zhao Liu <zhao1....@intel.com>
As the comment in qapi/error, passing @errp to error_prepend() requires
ERRP_GUARD():
* = Why, when and how to use ERRP_GUARD() =
*
* Without ERRP_GUARD(), use of the @errp parameter is restricted:
...
* - It should not be passed to error_prepend(), error_vprepend() or
* error_append_hint(), because that doesn't work with &error_fatal.
* ERRP_GUARD() lifts these restrictions.
*
* To use ERRP_GUARD(), add it right at the beginning of the function.
* @errp can then be used without worrying about the argument being
* NULL or &error_fatal.
ERRP_GUARD() could avoid the case when @errp is the pointer of
error_fatal, the user can't see this additional information, because
exit() happens in error_setg earlier than information is added [1].
The set_chr() passes @errp to error_prepend() without ERRP_GUARD().
As a PropertyInfo.set method, the @errp passed to set_chr() is so widely
sourced that it is necessary to protect it with ERRP_GUARD().
To avoid the issue like [1] said, add missing ERRP_GUARD() at the
beginning of this function.
[1]: Issue description in the commit message of commit ae7c80a7bd73
("error: New macro ERRP_GUARD()").
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: "Daniel P. Berrangé" <berra...@redhat.com>
Cc: Eduardo Habkost <edua...@habkost.net>
Signed-off-by: Zhao Liu <zhao1....@intel.com>
---
hw/core/qdev-properties-system.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index 1a396521d51f..545c3ceff7c9 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -242,6 +242,7 @@ static void get_chr(Object *obj, Visitor *v, const char
*name, void *opaque,
static void set_chr(Object *obj, Visitor *v, const char *name, void *opaque,
Error **errp)
{
+ ERRP_GUARD();
Property *prop = opaque;
CharBackend *be = object_field_prop_ptr(obj, prop);
Chardev *s;
--
2.34.1
