If the RX descriptor doesn't have any data, the output value of quote
from rswitch_rx() will be increased unexpectedily. So, fix it.
Reported-by: Volodymyr Babchuk <volodymyr_babchuk@xxxxxxxx>
Fixes: 3590918b5d07 ("net: ethernet: renesas: Add support for "Ethernet Switch"")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
drivers/net/ethernet/renesas/rswitch.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/renesas/rswitch.c b/drivers/net/ethernet/renesas/rswitch.c
index 853394e5bb8b..46d8d9c8fc19 100644
--- a/drivers/net/ethernet/renesas/rswitch.c
+++ b/drivers/net/ethernet/renesas/rswitch.c
@@ -702,13 +702,14 @@ static bool rswitch_rx(struct net_device *ndev, int *quota)
u16 pkt_len;
u32 get_ts;
+ if (*quota <= 0)
+ return true;
+
boguscnt = min_t(int, gq->ring_size, *quota);
limit = boguscnt;
desc = &gq->rx_ring[gq->cur];
while ((desc->desc.die_dt & DT_MASK) != DT_FEMPTY) {
- if (--boguscnt < 0)
- break;
dma_rmb();
pkt_len = le16_to_cpu(desc->desc.info_ds) & RX_DS;
skb = gq->skbs[gq->cur];
@@ -734,6 +735,9 @@ static bool rswitch_rx(struct net_device *ndev, int *quota)
gq->cur = rswitch_next_queue_index(gq, true, 1);
desc = &gq->rx_ring[gq->cur];
+
+ if (--boguscnt <= 0)
+ break;
}
num = rswitch_get_num_cur_queues(gq);
@@ -745,7 +749,7 @@ static bool rswitch_rx(struct net_device *ndev, int *quota)
goto err;
gq->dirty = rswitch_next_queue_index(gq, false, num);
- *quota -= limit - (++boguscnt);
+ *quota -= limit - boguscnt;
return boguscnt <= 0;
--
2.25.1
