Re: [PATCH v6 4/4] net: moxa: continue loop on skb allocation failure
From: Jonas Jensen Date: Mon, 25 Aug 2014 16:22:40 +0200 > If netdev_alloc_skb_ip_align() fails, subsequent code will > try to dereference an invalid pointer. > > Continue to next descriptor on error. > > While we're at it, > > 1. eliminate the chance of an endless loop, replace the main >loop with while(rx < budget) > > 2. use napi_complete() and remove the explicit napi_gro_flush() > > Signed-off-by: Jonas Jensen Applied. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH v6 4/4] net: moxa: continue loop on skb allocation failure
If netdev_alloc_skb_ip_align() fails, subsequent code will
try to dereference an invalid pointer.
Continue to next descriptor on error.
While we're at it,
1. eliminate the chance of an endless loop, replace the main
loop with while(rx < budget)
2. use napi_complete() and remove the explicit napi_gro_flush()
Signed-off-by: Jonas Jensen
---
Notes:
Applies to next-20140825
drivers/net/ethernet/moxa/moxart_ether.c | 12 +---
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/moxa/moxart_ether.c
b/drivers/net/ethernet/moxa/moxart_ether.c
index 983d019..2f12c88 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.c
+++ b/drivers/net/ethernet/moxa/moxart_ether.c
@@ -206,7 +206,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
int rx_head = priv->rx_head;
int rx = 0;
- while (1) {
+ while (rx < budget) {
desc = priv->rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
desc0 = readl(desc + RX_REG_OFFSET_DESC0);
@@ -218,7 +218,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
net_dbg_ratelimited("packet error\n");
priv->stats.rx_dropped++;
priv->stats.rx_errors++;
- continue;
+ goto rx_next;
}
len = desc0 & RX_DESC0_FRAME_LEN_MASK;
@@ -235,6 +235,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
net_dbg_ratelimited("netdev_alloc_skb_ip_align
failed\n");
priv->stats.rx_dropped++;
priv->stats.rx_errors++;
+ goto rx_next;
}
memcpy(skb->data, priv->rx_buf[rx_head], len);
@@ -249,18 +250,15 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
if (desc0 & RX_DESC0_MULTICAST)
priv->stats.multicast++;
+rx_next:
writel(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
rx_head = RX_NEXT(rx_head);
priv->rx_head = rx_head;
-
- if (rx >= budget)
- break;
}
if (rx < budget) {
- napi_gro_flush(napi, false);
- __napi_complete(napi);
+ napi_complete(napi);
}
priv->reg_imr |= RPKT_FINISH_M;
--
1.8.2.1
--
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[PATCH v6 4/4] net: moxa: continue loop on skb allocation failure
If netdev_alloc_skb_ip_align() fails, subsequent code will
try to dereference an invalid pointer.
Continue to next descriptor on error.
While we're at it,
1. eliminate the chance of an endless loop, replace the main
loop with while(rx budget)
2. use napi_complete() and remove the explicit napi_gro_flush()
Signed-off-by: Jonas Jensen jonas.jen...@gmail.com
---
Notes:
Applies to next-20140825
drivers/net/ethernet/moxa/moxart_ether.c | 12 +---
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/moxa/moxart_ether.c
b/drivers/net/ethernet/moxa/moxart_ether.c
index 983d019..2f12c88 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.c
+++ b/drivers/net/ethernet/moxa/moxart_ether.c
@@ -206,7 +206,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
int rx_head = priv-rx_head;
int rx = 0;
- while (1) {
+ while (rx budget) {
desc = priv-rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
desc0 = readl(desc + RX_REG_OFFSET_DESC0);
@@ -218,7 +218,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
net_dbg_ratelimited(packet error\n);
priv-stats.rx_dropped++;
priv-stats.rx_errors++;
- continue;
+ goto rx_next;
}
len = desc0 RX_DESC0_FRAME_LEN_MASK;
@@ -235,6 +235,7 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
net_dbg_ratelimited(netdev_alloc_skb_ip_align
failed\n);
priv-stats.rx_dropped++;
priv-stats.rx_errors++;
+ goto rx_next;
}
memcpy(skb-data, priv-rx_buf[rx_head], len);
@@ -249,18 +250,15 @@ static int moxart_rx_poll(struct napi_struct *napi, int
budget)
if (desc0 RX_DESC0_MULTICAST)
priv-stats.multicast++;
+rx_next:
writel(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
rx_head = RX_NEXT(rx_head);
priv-rx_head = rx_head;
-
- if (rx = budget)
- break;
}
if (rx budget) {
- napi_gro_flush(napi, false);
- __napi_complete(napi);
+ napi_complete(napi);
}
priv-reg_imr |= RPKT_FINISH_M;
--
1.8.2.1
--
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the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v6 4/4] net: moxa: continue loop on skb allocation failure
From: Jonas Jensen jonas.jen...@gmail.com Date: Mon, 25 Aug 2014 16:22:40 +0200 If netdev_alloc_skb_ip_align() fails, subsequent code will try to dereference an invalid pointer. Continue to next descriptor on error. While we're at it, 1. eliminate the chance of an endless loop, replace the main loop with while(rx budget) 2. use napi_complete() and remove the explicit napi_gro_flush() Signed-off-by: Jonas Jensen jonas.jen...@gmail.com Applied. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
