staging: wfx: fix possible overflow on jiffies comparaison

MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

It is recommended to use function time_*() to compare jiffies.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200115135338.14374-45-Jerome.Pouiller@silabs.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/wfx/data_tx.c b/drivers/staging/wfx/data_tx.c
index 6045929..704ebfe 100644 (file)
--- a/drivers/staging/wfx/data_tx.c
+++ b/drivers/staging/wfx/data_tx.c
@@ -270,8 +270,7 @@ void wfx_tx_policy_init(struct wfx_vif *wvif)
 static int wfx_alloc_link_id(struct wfx_vif *wvif, const u8 *mac)
 {
        int i, ret = 0;
-       unsigned long max_inactivity = 0;
-       unsigned long now = jiffies;
+       unsigned long oldest;
 
        spin_lock_bh(&wvif->ps_state_lock);
        for (i = 0; i < WFX_MAX_STA_IN_AP_MODE; ++i) {
@@ -280,13 +279,10 @@ static int wfx_alloc_link_id(struct wfx_vif *wvif, const u8 *mac)
                        break;
                } else if (wvif->link_id_db[i].status != WFX_LINK_HARD &&
                           !wvif->wdev->tx_queue_stats.link_map_cache[i + 1]) {
-                       unsigned long inactivity =
-                               now - wvif->link_id_db[i].timestamp;
-
-                       if (inactivity < max_inactivity)
-                               continue;
-                       max_inactivity = inactivity;
-                       ret = i + 1;
+                       if (!ret || time_after(oldest, wvif->link_id_db[i].timestamp)) {
+                               oldest = wvif->link_id_db[i].timestamp;
+                               ret = i + 1;
+                       }
                }
        }