1 files changed, 89 insertions, 28 deletions

diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index b2434b479846..3df203feb09c 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -1373,59 +1373,120 @@ static int ax88179_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 	u16 hdr_off;
 	u32 *pkt_hdr;
 
-	/* This check is no longer done by usbnet */
-	if (skb->len < dev->net->hard_header_len)
+	/* At the end of the SKB, there's a header telling us how many packets
+	 * are bundled into this buffer and where we can find an array of
+	 * per-packet metadata (which contains elements encoded into u16).
+	 */
+
+	/* SKB contents for current firmware:
+	 *   <packet 1> <padding>
+	 *   ...
+	 *   <packet N> <padding>
+	 *   <per-packet metadata entry 1> <dummy header>
+	 *   ...
+	 *   <per-packet metadata entry N> <dummy header>
+	 *   <padding2> <rx_hdr>
+	 *
+	 * where:
+	 *   <packet N> contains pkt_len bytes:
+	 *		2 bytes of IP alignment pseudo header
+	 *		packet received
+	 *   <per-packet metadata entry N> contains 4 bytes:
+	 *		pkt_len and fields AX_RXHDR_*
+	 *   <padding>	0-7 bytes to terminate at
+	 *		8 bytes boundary (64-bit).
+	 *   <padding2> 4 bytes to make rx_hdr terminate at
+	 *		8 bytes boundary (64-bit)
+	 *   <dummy-header> contains 4 bytes:
+	 *		pkt_len=0 and AX_RXHDR_DROP_ERR
+	 *   <rx-hdr>	contains 4 bytes:
+	 *		pkt_cnt and hdr_off (offset of
+	 *		  <per-packet metadata entry 1>)
+	 *
+	 * pkt_cnt is number of entrys in the per-packet metadata.
+	 * In current firmware there is 2 entrys per packet.
+	 * The first points to the packet and the
+	 *  second is a dummy header.
+	 * This was done probably to align fields in 64-bit and
+	 *  maintain compatibility with old firmware.
+	 * This code assumes that <dummy header> and <padding2> are
+	 *  optional.
+	 */
+
+	if (skb->len < 4)
 		return 0;
-
 	skb_trim(skb, skb->len - 4);
 	memcpy(&rx_hdr, skb_tail_pointer(skb), 4);
 	le32_to_cpus(&rx_hdr);
-
 	pkt_cnt = (u16)rx_hdr;
 	hdr_off = (u16)(rx_hdr >> 16);
+
+	if (pkt_cnt == 0)
+		return 0;
+
+	/* Make sure that the bounds of the metadata array are inside the SKB
+	 * (and in front of the counter at the end).
+	 */
+	if (pkt_cnt * 4 + hdr_off > skb->len)
+		return 0;
 	pkt_hdr = (u32 *)(skb->data + hdr_off);
 
-	while (pkt_cnt--) {
+	/* Packets must not overlap the metadata array */
+	skb_trim(skb, hdr_off);
+
+	for (; pkt_cnt > 0; pkt_cnt--, pkt_hdr++) {
+		u16 pkt_len_plus_padd;
 		u16 pkt_len;
 
 		le32_to_cpus(pkt_hdr);
 		pkt_len = (*pkt_hdr >> 16) & 0x1fff;
+		pkt_len_plus_padd = (pkt_len + 7) & 0xfff8;
+
+		/* Skip dummy header used for alignment
+		 */
+		if (pkt_len == 0)
+			continue;
+
+		if (pkt_len_plus_padd > skb->len)
+			return 0;
 
 		/* Check CRC or runt packet */
-		if ((*pkt_hdr & AX_RXHDR_CRC_ERR) ||
-		    (*pkt_hdr & AX_RXHDR_DROP_ERR)) {
-			skb_pull(skb, (pkt_len + 7) & 0xFFF8);
-			pkt_hdr++;
+		if ((*pkt_hdr & (AX_RXHDR_CRC_ERR | AX_RXHDR_DROP_ERR)) ||
+		    pkt_len < 2 + ETH_HLEN) {
+			dev->net->stats.rx_errors++;
+			skb_pull(skb, pkt_len_plus_padd);
 			continue;
 		}
 
-		if (pkt_cnt == 0) {
-			skb->len = pkt_len;
+		/* last packet */
+		if (pkt_len_plus_padd == skb->len) {
+			skb_trim(skb, pkt_len);
+
 			/* Skip IP alignment pseudo header */
 			skb_pull(skb, 2);
-			skb_set_tail_pointer(skb, skb->len);
-			skb->truesize = pkt_len + sizeof(struct sk_buff);
+
+			skb->truesize = SKB_TRUESIZE(pkt_len_plus_padd);
 			ax88179_rx_checksum(skb, pkt_hdr);
 			return 1;
 		}
 
 		ax_skb = skb_clone(skb, GFP_ATOMIC);
-		if (ax_skb) {
-			ax_skb->len = pkt_len;
-			/* Skip IP alignment pseudo header */
-			skb_pull(ax_skb, 2);
-			skb_set_tail_pointer(ax_skb, ax_skb->len);
-			ax_skb->truesize = pkt_len + sizeof(struct sk_buff);
-			ax88179_rx_checksum(ax_skb, pkt_hdr);
-			usbnet_skb_return(dev, ax_skb);
-		} else {
+		if (!ax_skb)
 			return 0;
-		}
+		skb_trim(ax_skb, pkt_len);
+
+		/* Skip IP alignment pseudo header */
+		skb_pull(ax_skb, 2);
+
+		skb->truesize = pkt_len_plus_padd +
+				SKB_DATA_ALIGN(sizeof(struct sk_buff));
+		ax88179_rx_checksum(ax_skb, pkt_hdr);
+		usbnet_skb_return(dev, ax_skb);
 
-		skb_pull(skb, (pkt_len + 7) & 0xFFF8);
-		pkt_hdr++;
+		skb_pull(skb, pkt_len_plus_padd);
 	}
-	return 1;
+
+	return 0;
 }
 
 static struct sk_buff *
@@ -1549,11 +1610,11 @@ static int ax88179_reset(struct usbnet *dev)
 
 	*tmp16 = AX_PHYPWR_RSTCTL_IPRL;
 	ax88179_write_cmd(dev, AX_ACCESS_MAC, AX_PHYPWR_RSTCTL, 2, 2, tmp16);
-	msleep(200);
+	msleep(500);
 
 	*tmp = AX_CLK_SELECT_ACS | AX_CLK_SELECT_BCS;
 	ax88179_write_cmd(dev, AX_ACCESS_MAC, AX_CLK_SELECT, 1, 1, tmp);
-	msleep(100);
+	msleep(200);
 
 	/* Ethernet PHY Auto Detach*/
 	ax88179_auto_detach(dev, 0);