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 cxl_fixed_memory_window_config(), @errp is dereferenced in 2
places without ERRP_GUARD():
fw->enc_int_ways = cxl_interleave_ways_enc(fw->num_targets, errp);
if (*errp) {
return;
}
and
fw->enc_int_gran =
cxl_interleave_granularity_enc(object->interleave_granularity,
errp);
if (*errp) {
return;
}
For the above 2 places, we check "*errp", because neither function
returns a suitable error code. And since machine_set_cfmw() - the caller
of cxl_fixed_memory_window_config() - doesn't get the NULL @errp
parameter as the "set" method of object property,
cxl_fixed_memory_window_config() hasn't triggered the bug that
dereferencing the NULL @errp.
To follow the requirement of @errp, add missing ERRP_GUARD() in
cxl_fixed_memory_window_config().
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240223085653.1255438-2-zhao1.liu@linux.intel.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
5c7eedf53d