[PATCH 63/64] iwlwifi: dbg_ini: Split memcpy() to avoid multi-field write

[Kees Cook]

To avoid a run-time false positive in the stricter FORTIFY_SOURCE
memcpy() checks, split the memcpy() into the struct and the data.
Additionally switch the data member to a flexible array to follow
modern language conventions.

Signed-off-by: Kees Cook <keescook at chromium.org>
---
 drivers/net/wireless/intel/iwlwifi/fw/file.h     | 2 +-
 drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/file.h b/drivers/net/wireless/intel/iwlwifi/fw/file.h
index 9a8c7b7a0816..226ccd3a6612 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/file.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/file.h
@@ -116,7 +116,7 @@ enum iwl_ucode_tlv_type {
 struct iwl_ucode_tlv {
 	__le32 type;		/* see above */
 	__le32 length;		/* not including type/length fields */
-	u8 data[0];
+	u8 data[];
 };
 
 #define IWL_TLV_UCODE_MAGIC		0x0a4c5749
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
index 0ddd255a8cc1..f4efddf3e3c3 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
@@ -71,7 +71,8 @@ static int iwl_dbg_tlv_add(const struct iwl_ucode_tlv *tlv,
 	if (!node)
 		return -ENOMEM;
 
-	memcpy(&node->tlv, tlv, sizeof(node->tlv) + len);
+	memcpy(&node->tlv, tlv, sizeof(node->tlv));
+	memcpy(node->tlv.data, tlv->data, len);
 	list_add_tail(&node->list, list);
 
 	return 0;
-- 
2.30.2