[PATCH v2 44/65] staging: wfx: fix possible overflow on jiffies comparaison

From: JÃrÃme Pouiller
Date: Wed Jan 15 2020 - 08:58:48 EST


From: JÃrÃme Pouiller <jerome.pouiller@xxxxxxxxxx>

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

Signed-off-by: JÃrÃme Pouiller <jerome.pouiller@xxxxxxxxxx>
---
drivers/staging/wfx/data_tx.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/wfx/data_tx.c b/drivers/staging/wfx/data_tx.c
index 60459299a3a9..704ebfe1cd05 100644
--- 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;
+ }
}
}

--
2.25.0