wifi: iwlwifi: dbg-tlv: ensure NUL termination

[ Upstream commit ea1d166fae14e05d49ffb0ea9fcd4658f8d3dcea ]

The iwl_fw_ini_debug_info_tlv is used as a string, so we must
ensure the string is terminated correctly before using it.

Fixes: a9248de424 ("iwlwifi: dbg_ini: add TLV allocation new API support")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240128084842.be15e858ee89.Ibff93429cf999eafc7b26f3eef4c055dc84984a0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c

@@ -99,6 +99,12 @@ static int iwl_dbg_tlv_alloc_debug_info(struct iwl_trans *trans,
 	if (le32_to_cpu(tlv->length) != sizeof(*debug_info))
 		return -EINVAL;
 
+	/* we use this as a string, ensure input was NUL terminated */
+	if (strnlen(debug_info->debug_cfg_name,
+		    sizeof(debug_info->debug_cfg_name)) ==
+			sizeof(debug_info->debug_cfg_name))
+		return -EINVAL;
+
 	IWL_DEBUG_FW(trans, "WRT: Loading debug cfg: %s\n",
 		     debug_info->debug_cfg_name);