[PATCH 4.9 03/12] staging: wilc1000: simplify vif[i]->ndev accesses

Greg Kroah-Hartman
2017-08-31T15:46:05Z

4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Arnd Bergmann <arnd@arndb.de>

commit 735bb39ca3bed8469b3b3a42d8cc57bdb9fc4dd7 upstream.

With gcc-7, I got a new warning for this driver:

wilc1000/linux_wlan.c: In function 'wilc_netdev_cleanup':
wilc1000/linux_wlan.c:1224:15: error: 'vif[1]' may be used uninitialized in this function [-Werror=maybe-uninitialized]
wilc1000/linux_wlan.c:1224:15: error: 'vif[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized]

A closer look at the function reveals that it's more complex than
it needs to be, given that based on how the device is created
we always get

netdev_priv(vif->ndev) == vif

Based on this assumption, I found a few other places in the same file
that can be simplified. That code appears to be a relic from times
when the assumption above was not valid.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/staging/wilc1000/linux_wlan.c | 34 +++++++++-------------------------
1 file changed, 9 insertions(+), 25 deletions(-)

--- a/drivers/staging/wilc1000/linux_wlan.c
+++ b/drivers/staging/wilc1000/linux_wlan.c
@@ -269,23 +269,12 @@ static struct net_device *get_if_handler

int wilc_wlan_set_bssid(struct net_device *wilc_netdev, u8 *bssid, u8 mode)
{
- int i = 0;
- int ret = -1;
- struct wilc_vif *vif;
- struct wilc *wilc;
-
- vif = netdev_priv(wilc_netdev);
- wilc = vif->wilc;
+ struct wilc_vif *vif = netdev_priv(wilc_netdev);

- for (i = 0; i < wilc->vif_num; i++)
- if (wilc->vif[i]->ndev == wilc_netdev) {
- memcpy(wilc->vif[i]->bssid, bssid, 6);
- wilc->vif[i]->mode = mode;
- ret = 0;
- break;
- }
+ memcpy(vif->bssid, bssid, 6);
+ vif->mode = mode;

- return ret;
+ return 0;
}

int wilc_wlan_get_num_conn_ifcs(struct wilc *wilc)
@@ -1212,16 +1201,11 @@ void WILC_WFI_mgmt_rx(struct wilc *wilc,

void wilc_netdev_cleanup(struct wilc *wilc)
{
- int i = 0;
- struct wilc_vif *vif[NUM_CONCURRENT_IFC];
+ int i;

- if (wilc && (wilc->vif[0]->ndev || wilc->vif[1]->ndev)) {
+ if (wilc && (wilc->vif[0]->ndev || wilc->vif[1]->ndev))
unregister_inetaddr_notifier(&g_dev_notifier);

- for (i = 0; i < NUM_CONCURRENT_IFC; i++)
- vif[i] = netdev_priv(wilc->vif[i]->ndev);
- }
-
if (wilc && wilc->firmware) {
release_firmware(wilc->firmware);
wilc->firmware = NULL;
@@ -1230,7 +1214,7 @@ void wilc_netdev_cleanup(struct wilc *wi
if (wilc && (wilc->vif[0]->ndev || wilc->vif[1]->ndev)) {
for (i = 0; i < NUM_CONCURRENT_IFC; i++)
if (wilc->vif[i]->ndev)
- if (vif[i]->mac_opened)
+ if (wilc->vif[i]->mac_opened)
wilc_mac_close(wilc->vif[i]->ndev);

for (i = 0; i < NUM_CONCURRENT_IFC; i++) {
@@ -1278,9 +1262,9 @@ int wilc_netdev_init(struct wilc **wilc,

vif->idx = wl->vif_num;
vif->wilc = *wilc;
+ vif->ndev = ndev;
wl->vif[i] = vif;
- wl->vif[wl->vif_num]->ndev = ndev;
- wl->vif_num++;
+ wl->vif_num = i;
ndev->netdev_ops = &wilc_netdev_ops;

{