lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <1197235034.20251.10.camel@dell>
Date:	Sun, 09 Dec 2007 13:17:14 -0800
From:	"Michael Chan" <mchan@...adcom.com>
To:	davem@...emloft.net
cc:	netdev@...r.kernel.org
Subject: [PATCH 2/3][BNX2]: Fix RX packet rot.

[BNX2]: Fix RX packet rot.

Packets can be left in the RX ring if the NAPI budget is reached.
This is caused by storing the latest rx index at the beginning of
bnx2_rx_int().  We may not process all the work up to this index
if the budget is reached and so some packets in the RX ring may rot
when we later check for more work using this stored rx index.

The fix is to not store this latest hw index and only store the
processed rx index.  We use a new function bnx2_get_hw_rx_cons()
to fetch the latest hw rx index.

Signed-off-by: Michael Chan <mchan@...adcom.com>

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index a4f3832..f9eea6e 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -2387,18 +2387,24 @@ bnx2_reuse_rx_skb(struct bnx2 *bp, struct sk_buff *skb,
 	prod_bd->rx_bd_haddr_lo = cons_bd->rx_bd_haddr_lo;
 }
 
+static inline u16
+bnx2_get_hw_rx_cons(struct bnx2 *bp)
+{
+	u16 cons = bp->status_blk->status_rx_quick_consumer_index0;
+
+	if (unlikely((cons & MAX_RX_DESC_CNT) == MAX_RX_DESC_CNT))
+		cons++;
+	return cons;
+}
+
 static int
 bnx2_rx_int(struct bnx2 *bp, int budget)
 {
-	struct status_block *sblk = bp->status_blk;
 	u16 hw_cons, sw_cons, sw_ring_cons, sw_prod, sw_ring_prod;
 	struct l2_fhdr *rx_hdr;
 	int rx_pkt = 0;
 
-	hw_cons = bp->hw_rx_cons = sblk->status_rx_quick_consumer_index0;
-	if ((hw_cons & MAX_RX_DESC_CNT) == MAX_RX_DESC_CNT) {
-		hw_cons++;
-	}
+	hw_cons = bnx2_get_hw_rx_cons(bp);
 	sw_cons = bp->rx_cons;
 	sw_prod = bp->rx_prod;
 
@@ -2515,10 +2521,7 @@ next_rx:
 
 		/* Refresh hw_cons to see if there is new work */
 		if (sw_cons == hw_cons) {
-			hw_cons = bp->hw_rx_cons =
-				sblk->status_rx_quick_consumer_index0;
-			if ((hw_cons & MAX_RX_DESC_CNT) == MAX_RX_DESC_CNT)
-				hw_cons++;
+			hw_cons = bnx2_get_hw_rx_cons(bp);
 			rmb();
 		}
 	}
@@ -2622,7 +2625,7 @@ bnx2_has_work(struct bnx2 *bp)
 {
 	struct status_block *sblk = bp->status_blk;
 
-	if ((sblk->status_rx_quick_consumer_index0 != bp->hw_rx_cons) ||
+	if ((bnx2_get_hw_rx_cons(bp) != bp->rx_cons) ||
 	    (sblk->status_tx_quick_consumer_index0 != bp->hw_tx_cons))
 		return 1;
 
@@ -2655,7 +2658,7 @@ static int bnx2_poll_work(struct bnx2 *bp, int work_done, int budget)
 	if (sblk->status_tx_quick_consumer_index0 != bp->hw_tx_cons)
 		bnx2_tx_int(bp);
 
-	if (sblk->status_rx_quick_consumer_index0 != bp->hw_rx_cons)
+	if (bnx2_get_hw_rx_cons(bp) != bp->rx_cons)
 		work_done += bnx2_rx_int(bp, budget - work_done);
 
 	return work_done;
@@ -4177,7 +4180,6 @@ bnx2_init_rx_ring(struct bnx2 *bp)
 
 	ring_prod = prod = bp->rx_prod = 0;
 	bp->rx_cons = 0;
-	bp->hw_rx_cons = 0;
 	bp->rx_prod_bseq = 0;
 
 	for (i = 0; i < bp->rx_max_ring; i++) {
diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h
index 1dce0d1..30ba366 100644
--- a/drivers/net/bnx2.h
+++ b/drivers/net/bnx2.h
@@ -6513,7 +6513,6 @@ struct bnx2 {
 	u32			rx_prod_bseq;
 	u16			rx_prod;
 	u16			rx_cons;
-	u16			hw_rx_cons;
 
 	u32			rx_csum;
 


--
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

Powered by Openwall GNU/*/Linux Powered by OpenVZ