wifi: iwlwifi: mvm: check firmware response size

Check the firmware response size for responses to the
memory read/write command in debugfs before using it.

Fixes: 2b55f43f ("iwlwifi: mvm: Add mem debugfs entry")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230417113648.0d56fcaf68ee.I70e9571f3ed7263929b04f8fabad23c9b999e4ea@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c

@@ -1961,6 +1961,11 @@ static ssize_t iwl_dbgfs_mem_read(struct file *file, char __user *user_buf,
 	if (ret < 0)
 		return ret;
 
+	if (iwl_rx_packet_payload_len(hcmd.resp_pkt) < sizeof(*rsp)) {
+		ret = -EIO;
+		goto out;
+	}
+
 	rsp = (void *)hcmd.resp_pkt->data;
 	if (le32_to_cpu(rsp->status) != DEBUG_MEM_STATUS_SUCCESS) {
 		ret = -ENXIO;
@@ -2037,6 +2042,11 @@ static ssize_t iwl_dbgfs_mem_write(struct file *file,
 	if (ret < 0)
 		return ret;
 
+	if (iwl_rx_packet_payload_len(hcmd.resp_pkt) < sizeof(*rsp)) {
+		ret = -EIO;
+		goto out;
+	}
+
 	rsp = (void *)hcmd.resp_pkt->data;
 	if (rsp->status != DEBUG_MEM_STATUS_SUCCESS) {
 		ret = -ENXIO;