[PATCH v2][next] wifi: iwlwifi: mvm: Use __counted_by() and avoid -Wfamnae warnings

Gustavo A. R. Silva
2024-08-09T19:24:24Z

-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

So, use the `DEFINE_FLEX()` helper for multiple on-stack definitions
of flexible structures where the size of their flexible-array members
are known at compile-time, and refactor the rest of the code,
accordingly.

In order to allow for the use of `DEFINE_FLEX()`, a couple of
structures were annotated with the `__counted_by()` attribute.

With these changes, fix the following warnings:
drivers/net/wireless/intel/iwlwifi/mvm/d3.c:124:52: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
drivers/net/wireless/intel/iwlwifi/mvm/d3.c:2053:51: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
drivers/net/wireless/intel/iwlwifi/mvm/d3.c:2148:43: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
drivers/net/wireless/intel/iwlwifi/mvm/d3.c:2211:43: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
Changes in v2:
- Fix use of keylen variable.

.../net/wireless/intel/iwlwifi/fw/api/sta.h | 2 +-
drivers/net/wireless/intel/iwlwifi/mvm/d3.c | 126 ++++++++----------
drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 2 +-
include/net/mac80211.h | 2 +-
4 files changed, 61 insertions(+), 71 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/api/sta.h b/drivers/net/wireless/intel/iwlwifi/fw/api/sta.h
index d7f8a276b683..fe6bd34fefa3 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/api/sta.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/api/sta.h
@@ -479,7 +479,7 @@ struct iwl_mvm_wep_key_cmd {
u8 decryption_type;
u8 flags;
u8 reserved;
- struct iwl_mvm_wep_key wep_key[];
+ struct iwl_mvm_wep_key wep_key[] __counted_by(num_keys);
} __packed; /* SEC_CURR_WEP_KEY_CMD_API_S_VER_2 */

/**
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
index b4d650583ac2..b19579dd8de3 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
@@ -120,19 +120,15 @@ static void iwl_mvm_wowlan_program_keys(struct ieee80211_hw *hw,
switch (key->cipher) {
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104: { /* hack it for now */
- struct {
- struct iwl_mvm_wep_key_cmd wep_key_cmd;
- struct iwl_mvm_wep_key wep_key;
- } __packed wkc = {
- .wep_key_cmd.mac_id_n_color =
- cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id,
- mvmvif->color)),
- .wep_key_cmd.num_keys = 1,
- /* firmware sets STA_KEY_FLG_WEP_13BYTES */
- .wep_key_cmd.decryption_type = STA_KEY_FLG_WEP,
- .wep_key.key_index = key->keyidx,
- .wep_key.key_size = key->keylen,
- };
+ DEFINE_FLEX(struct iwl_mvm_wep_key_cmd, wkc, wep_key, num_keys, 1);
+
+ wkc->mac_id_n_color =
+ cpu_to_le32(FW_CMD_ID_AND_COLOR(mvmvif->id,
+ mvmvif->color));
+ /* firmware sets STA_KEY_FLG_WEP_13BYTES */
+ wkc->decryption_type = STA_KEY_FLG_WEP;
+ wkc->wep_key[0].key_index = key->keyidx;
+ wkc->wep_key[0].key_size = key->keylen;

/*
* This will fail -- the key functions don't set support
@@ -142,18 +138,18 @@ static void iwl_mvm_wowlan_program_keys(struct ieee80211_hw *hw,
if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
break;

- memcpy(&wkc.wep_key.key[3], key->key, key->keylen);
+ memcpy(&wkc->wep_key[0].key[3], key->key, key->keylen);
if (key->keyidx == mvmvif->tx_key_idx) {
/* TX key must be at offset 0 */
- wkc.wep_key.key_offset = 0;
+ wkc->wep_key[0].key_offset = 0;
} else {
/* others start at 1 */
data->wep_key_idx++;
- wkc.wep_key.key_offset = data->wep_key_idx;
+ wkc->wep_key[0].key_offset = data->wep_key_idx;
}

mutex_lock(&mvm->mutex);
- ret = iwl_mvm_send_cmd_pdu(mvm, WEP_KEY, 0, sizeof(wkc), &wkc);
+ ret = iwl_mvm_send_cmd_pdu(mvm, WEP_KEY, 0, __struct_size(wkc), wkc);
data->error = ret != 0;

mvm->ptk_ivlen = key->iv_len;
@@ -2049,10 +2045,8 @@ static bool iwl_mvm_mlo_gtk_rekey(struct iwl_wowlan_status_data *status,
struct iwl_wowlan_mlo_gtk *mlo_key = &status->mlo_keys[i];
struct ieee80211_key_conf *key, *old_key;
struct ieee80211_key_seq seq;
- struct {
- struct ieee80211_key_conf conf;
- u8 key[32];
- } conf = {};
+ DEFINE_FLEX(struct ieee80211_key_conf, conf, key, keylen,
+ WOWLAN_KEY_MAX_SIZE);
u16 flags = le16_to_cpu(mlo_key->flags);
int j, link_id, key_id, key_type;

@@ -2069,40 +2063,40 @@ static bool iwl_mvm_mlo_gtk_rekey(struct iwl_wowlan_status_data *status,
key_type >= WOWLAN_MLO_GTK_KEY_NUM_TYPES))
continue;

- conf.conf.cipher = old_keys->cipher[link_id][key_type];
+ conf->cipher = old_keys->cipher[link_id][key_type];
/* WARN_ON? */
- if (!conf.conf.cipher)
+ if (!conf->cipher)
continue;

- conf.conf.keylen = 0;
- switch (conf.conf.cipher) {
+ conf->keylen = 0;
+ switch (conf->cipher) {
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_GCMP:
- conf.conf.keylen = WLAN_KEY_LEN_CCMP;
+ conf->keylen = WLAN_KEY_LEN_CCMP;
break;
case WLAN_CIPHER_SUITE_GCMP_256:
- conf.conf.keylen = WLAN_KEY_LEN_GCMP_256;
+ conf->keylen = WLAN_KEY_LEN_GCMP_256;
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_GMAC_128;
+ conf->keylen = WLAN_KEY_LEN_BIP_GMAC_128;
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_GMAC_256;
+ conf->keylen = WLAN_KEY_LEN_BIP_GMAC_256;
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
- conf.conf.keylen = WLAN_KEY_LEN_AES_CMAC;
+ conf->keylen = WLAN_KEY_LEN_AES_CMAC;
break;
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_CMAC_256;
+ conf->keylen = WLAN_KEY_LEN_BIP_CMAC_256;
break;
}

- if (WARN_ON(!conf.conf.keylen ||
- conf.conf.keylen > sizeof(conf.key)))
+ if (WARN_ON(!conf->keylen ||
+ conf->keylen > WOWLAN_KEY_MAX_SIZE))
continue;

- memcpy(conf.conf.key, mlo_key->key, conf.conf.keylen);
- conf.conf.keyidx = key_id;
+ memcpy(conf->key, mlo_key->key, conf->keylen);
+ conf->keyidx = key_id;

old_key = old_keys->key[link_id][key_id];
if (old_key) {
@@ -2114,7 +2108,7 @@ static bool iwl_mvm_mlo_gtk_rekey(struct iwl_wowlan_status_data *status,

IWL_DEBUG_WOWLAN(mvm, "Add MLO key id %d, link id %d\n",
key_id, link_id);
- key = ieee80211_gtk_rekey_add(vif, &conf.conf, link_id);
+ key = ieee80211_gtk_rekey_add(vif, conf, link_id);
if (WARN_ON(IS_ERR(key))) {
ret = false;
goto out;
@@ -2144,30 +2138,28 @@ static bool iwl_mvm_gtk_rekey(struct iwl_wowlan_status_data *status,
{
int i, j;
struct ieee80211_key_conf *key;
- struct {
- struct ieee80211_key_conf conf;
- u8 key[32];
- } conf = {
- .conf.cipher = gtk_cipher,
- };
+ DEFINE_FLEX(struct ieee80211_key_conf, conf, key, keylen,
+ WOWLAN_KEY_MAX_SIZE);
int link_id = vif->active_links ? __ffs(vif->active_links) : -1;

+ conf->cipher = gtk_cipher;
+
BUILD_BUG_ON(WLAN_KEY_LEN_CCMP != WLAN_KEY_LEN_GCMP);
- BUILD_BUG_ON(sizeof(conf.key) < WLAN_KEY_LEN_CCMP);
- BUILD_BUG_ON(sizeof(conf.key) < WLAN_KEY_LEN_GCMP_256);
- BUILD_BUG_ON(sizeof(conf.key) < WLAN_KEY_LEN_TKIP);
- BUILD_BUG_ON(sizeof(conf.key) < sizeof(status->gtk[0].key));
+ BUILD_BUG_ON(conf->keylen < WLAN_KEY_LEN_CCMP);
+ BUILD_BUG_ON(conf->keylen < WLAN_KEY_LEN_GCMP_256);
+ BUILD_BUG_ON(conf->keylen < WLAN_KEY_LEN_TKIP);
+ BUILD_BUG_ON(conf->keylen < sizeof(status->gtk[0].key));

switch (gtk_cipher) {
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_GCMP:
- conf.conf.keylen = WLAN_KEY_LEN_CCMP;
+ conf->keylen = WLAN_KEY_LEN_CCMP;
break;
case WLAN_CIPHER_SUITE_GCMP_256:
- conf.conf.keylen = WLAN_KEY_LEN_GCMP_256;
+ conf->keylen = WLAN_KEY_LEN_GCMP_256;
break;
case WLAN_CIPHER_SUITE_TKIP:
- conf.conf.keylen = WLAN_KEY_LEN_TKIP;
+ conf->keylen = WLAN_KEY_LEN_TKIP;
break;
default:
WARN_ON(1);
@@ -2177,14 +2169,14 @@ static bool iwl_mvm_gtk_rekey(struct iwl_wowlan_status_data *status,
if (!status->gtk[i].len)
continue;

- conf.conf.keyidx = status->gtk[i].id;
+ conf->keyidx = status->gtk[i].id;
IWL_DEBUG_WOWLAN(mvm,
"Received from FW GTK cipher %d, key index %d\n",
- conf.conf.cipher, conf.conf.keyidx);
- memcpy(conf.conf.key, status->gtk[i].key,
+ conf->cipher, conf->keyidx);
+ memcpy(conf->key, status->gtk[i].key,
sizeof(status->gtk[i].key));

- key = ieee80211_gtk_rekey_add(vif, &conf.conf, link_id);
+ key = ieee80211_gtk_rekey_add(vif, conf, link_id);
if (IS_ERR(key))
return false;

@@ -2207,41 +2199,39 @@ iwl_mvm_d3_igtk_bigtk_rekey_add(struct iwl_wowlan_status_data *status,
struct iwl_multicast_key_data *key_data)
{
struct ieee80211_key_conf *key_config;
- struct {
- struct ieee80211_key_conf conf;
- u8 key[WOWLAN_KEY_MAX_SIZE];
- } conf = {
- .conf.cipher = cipher,
- .conf.keyidx = key_data->id,
- };
+ DEFINE_FLEX(struct ieee80211_key_conf, conf, key, keylen,
+ WOWLAN_KEY_MAX_SIZE);
struct ieee80211_key_seq seq;
int link_id = vif->active_links ? __ffs(vif->active_links) : -1;

+ conf->cipher = cipher;
+ conf->keyidx = key_data->id;
+
if (!key_data->len)
return true;

- iwl_mvm_d3_set_igtk_bigtk_ipn(key_data, &seq, conf.conf.cipher);
+ iwl_mvm_d3_set_igtk_bigtk_ipn(key_data, &seq, conf->cipher);

switch (cipher) {
case WLAN_CIPHER_SUITE_BIP_GMAC_128:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_GMAC_128;
+ conf->keylen = WLAN_KEY_LEN_BIP_GMAC_128;
break;
case WLAN_CIPHER_SUITE_BIP_GMAC_256:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_GMAC_256;
+ conf->keylen = WLAN_KEY_LEN_BIP_GMAC_256;
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
- conf.conf.keylen = WLAN_KEY_LEN_AES_CMAC;
+ conf->keylen = WLAN_KEY_LEN_AES_CMAC;
break;
case WLAN_CIPHER_SUITE_BIP_CMAC_256:
- conf.conf.keylen = WLAN_KEY_LEN_BIP_CMAC_256;
+ conf->keylen = WLAN_KEY_LEN_BIP_CMAC_256;
break;
default:
WARN_ON(1);
}
- BUILD_BUG_ON(sizeof(conf.key) < sizeof(key_data->key));
- memcpy(conf.conf.key, key_data->key, conf.conf.keylen);
+ BUILD_BUG_ON(WOWLAN_KEY_MAX_SIZE < sizeof(key_data->key));
+ memcpy(conf->key, key_data->key, conf->keylen);

- key_config = ieee80211_gtk_rekey_add(vif, &conf.conf, link_id);
+ key_config = ieee80211_gtk_rekey_add(vif, conf, link_id);
if (IS_ERR(key_config))
return false;
ieee80211_set_key_rx_seq(key_config, 0, &seq);
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 15e64d94d6ea..1502f577a942 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -4350,8 +4350,8 @@ int iwl_mvm_add_pasn_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
goto out;

keyconf->cipher = cipher;
- memcpy(keyconf->key, key, key_len);
keyconf->keylen = key_len;
+ memcpy(keyconf->key, key, keyconf->keylen);
keyconf->flags = IEEE80211_KEY_FLAG_PAIRWISE;

if (mld) {
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0a04eaf5343c..d3f6056daf8a 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2222,7 +2222,7 @@ struct ieee80211_key_conf {
u16 flags;
s8 link_id;
u8 keylen;
- u8 key[];
+ u8 key[] __counted_by(keylen);
};

#define IEEE80211_MAX_PN_LEN 16
--
2.34.1