wifi: iwlwifi: fix format-truncation warnings

On v6.6-rc4 with GCC 13.2 I see:

drivers/net/wireless/intel/iwlwifi/dvm/main.c:1467:19: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size 32 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/dvm/main.c:1465:9: note: 'snprintf' output between 1 and 64 bytes into a destination of size 32 drivers/net/wireless/intel/iwlwifi/mvm/ops.c:1307:19: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size 32 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/mvm/ops.c:1305:9: note: 'snprintf' output between 1 and 64 bytes into a destination of size 32 drivers/net/wireless/intel/iwlwifi/iwl-drv.c:549:33: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size between 48 and 56 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/iwl-drv.c:547:9: note: 'snprintf' output 9 or more bytes (assuming 80) into a destination of size 64 drivers/net/wireless/intel/iwlwifi/iwl-drv.c:729:33: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size between 48 and 56 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/iwl-drv.c:727:9: note: 'snprintf' output 9 or more bytes (assuming 80) into a destination of size 64 drivers/net/wireless/intel/iwlwifi/iwl-drv.c:989:51: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size between 46 and 58 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/iwl-drv.c:987:33: note: 'snprintf' output between 7 and 82 bytes into a destination of size 64 drivers/net/wireless/intel/iwlwifi/iwl-drv.c:984:53: warning: '%s' directive output may be truncated writing up to 63 bytes into a region of size between 40 and 50 [-Wformat-truncation=] drivers/net/wireless/intel/iwlwifi/iwl-drv.c:982:33: note: 'snprintf' output between 15 and 88 bytes into a destination of size 64

Two of the warnings were easy to fix by using strscpy(). But the rest were more challening. For now I was only able to come up with artificial testing of snprintf() return value but that doesn't make really sense. I marked the ugly once "FIXME" in the code.

Any ideas how to fix the warnings properly?

Compile tested only.

---
 drivers/net/wireless/intel/iwlwifi/dvm/main.c |  5 +-
 drivers/net/wireless/intel/iwlwifi/iwl-drv.c  | 64 +++++++++++--------
 drivers/net/wireless/intel/iwlwifi/mvm/ops.c  |  5 +-
 3 files changed, 41 insertions(+), 33 deletions(-)

index a873be109f43..6b252f19b641 100644
@@ -1462,9 +1462,8 @@ static struct iwl_op_mode *iwl_op_mode_dvm_start(struct iwl_trans *trans,
 	iwl_power_initialize(priv);
 	iwl_tt_initialize(priv);
 
-	snprintf(priv->hw->wiphy->fw_version,
-		 sizeof(priv->hw->wiphy->fw_version),
-		 "%s", fw->fw_version);
+	strscpy(priv->hw->wiphy->fw_version, fw->fw_version,
+		sizeof(priv->hw->wiphy->fw_version));
 
 	priv->new_scan_threshold_behaviour =
 		!!(ucode_flags & IWL_UCODE_TLV_FLAGS_NEWSCAN);

index 465090f67aaf..3864aaf7c1ac 100644
@@ -1302,9 +1302,8 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
 	trans_cfg.cmd_q_wdg_timeout =
 		iwl_mvm_get_wd_timeout(mvm, NULL, false, true);
 
-	snprintf(mvm->hw->wiphy->fw_version,
-		 sizeof(mvm->hw->wiphy->fw_version),
-		 "%s", fw->fw_version);
+	strscpy(mvm->hw->wiphy->fw_version, fw->fw_version,
+		sizeof(mvm->hw->wiphy->fw_version));
 
 	trans_cfg.fw_reset_handshake = fw_has_capa(&mvm->fw->ucode_capa,
 						   IWL_UCODE_TLV_CAPA_FW_RESET_HANDSHAKE);

base-commit: 618071ae0f7e8c1aeb9b1b1e9ee876bcc3f045fc

2.39.2

I didn't notice that Gregory had already submitted a patch:

https://patchwork.kernel.org/project/linux-wireless/patch/20231012153950.f4465b4b4e2b.Idced2e8d63c492872edcde1a3ce2cdd6cc0f8eb7@changeid/

https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches