[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <4AAD7B3D.7010403@ring3k.org>
Date: Mon, 14 Sep 2009 08:07:41 +0900
From: Mike McCormack <mikem@...g3k.org>
To: Stephen Hemminger <shemminger@...ux-foundation.org>
CC: netdev@...r.kernel.org
Subject: [PATCH resend] sky2: Account for VLAN tag in tx_le_req
With VLAN enabled, tx_le_req could return fewer list elements than required,
leading to a potential wrap around of the transmit ring buffer.
Signed-off-by: Mike McCormack <mikem@...g3k.org>
---
drivers/net/sky2.c | 14 +++++++++++---
1 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 00bc65a..c8ebc03 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1563,7 +1563,7 @@ static inline int tx_avail(const struct sky2_port *sky2)
}
/* Estimate of number of transmit list elements required */
-static unsigned tx_le_req(const struct sk_buff *skb)
+static unsigned tx_le_req(const struct sk_buff *skb, int vlan_tag)
{
unsigned count;
@@ -1573,6 +1573,9 @@ static unsigned tx_le_req(const struct sk_buff *skb)
if (skb_is_gso(skb))
++count;
+ else if (sizeof(dma_addr_t) == sizeof(u32) && vlan_tag)
+ ++count;
+
if (skb->ip_summed == CHECKSUM_PARTIAL)
++count;
@@ -1611,8 +1614,13 @@ static netdev_tx_t sky2_xmit_frame(struct sk_buff *skb,
u16 slot;
u16 mss;
u8 ctrl;
+ unsigned vlan_tag = 0;
+
+#ifdef SKY2_VLAN_TAG_USED
+ vlan_tag = sky2->vlgrp && vlan_tx_tag_present(skb);
+#endif
- if (unlikely(tx_avail(sky2) < tx_le_req(skb)))
+ if (unlikely(tx_avail(sky2) < tx_le_req(skb, vlan_tag)))
return NETDEV_TX_BUSY;
len = skb_headlen(skb);
@@ -1657,7 +1665,7 @@ static netdev_tx_t sky2_xmit_frame(struct sk_buff *skb,
ctrl = 0;
#ifdef SKY2_VLAN_TAG_USED
/* Add VLAN tag, can piggyback on LRGLEN or ADDR64 */
- if (sky2->vlgrp && vlan_tx_tag_present(skb)) {
+ if (vlan_tag) {
if (!le) {
le = get_tx_le(sky2, &slot);
le->addr = 0;
--
1.5.6.5
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists