On 23/2/24 09:56, Zhao Liu wrote:
From: Zhao Liu <zhao1....@intel.com>As the comment in qapi/error, dereferencing @errp requires ERRP_GUARD(): * = Why, when and how to use ERRP_GUARD() = * * Without ERRP_GUARD(), use of the @errp parameter is restricted: * - It must not be dereferenced, because it may be null. ... * 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. * * Using it when it's not needed is safe, but please avoid cluttering * the source with useless code. But in trng_prop_fault_event_set, @errp is dereferenced without ERRP_GUARD(): visit_type_uint32(v, name, events, errp); if (*errp) { return; } Currently, since trng_prop_fault_event_set() doesn't get the NULL @errp parameter as a "set" method of object property, it hasn't triggered the bug that dereferencing the NULL @errp. And since visit_type_uint32() returns bool, check the returned bool directly instead of dereferencing @errp, then we needn't the add missing ERRP_GUARD(). Suggested-by: Markus Armbruster <arm...@redhat.com> Signed-off-by: Zhao Liu <zhao1....@intel.com> --- Suggested by credit: Markus: Referred his explanation about ERRP_GUARD(). --- v2: * Add the @errp dereference code in commit message to make review easier. (Markus) * Check the returned bool instead of dereferencing @errp. (Markus) --- hw/misc/xlnx-versal-trng.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
