net: macb: Handle errors in RX path

index 4d73110..81429df 100644
@@ -755,6 +755,17 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag,
 		macb_rx_ring_wrap(first_frag),
 		macb_rx_ring_wrap(last_frag), len);
 
+	if (!(desc->ctrl & MACB_BIT(RX_EOF))) {
+		netdev_vdbg(bp->dev, "macb_rx_frame missing EOF\n");
+		return -EIO;
+	}
+
+	desc = macb_rx_desc(bp, first_frag);
+	if (!(desc->ctrl & MACB_BIT(RX_SOF))) {
+		netdev_vdbg(bp->dev, "macb_rx_frame missing SOF\n");
+		return -EIO;
+	}
+
 	/*
 	 * The ethernet header starts NET_IP_ALIGN bytes into the
 	 * first buffer. Since the header is 14 bytes, this makes the

@@ -789,7 +800,10 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag,
 		unsigned int frag_len = bp->rx_buffer_size;
 
 		if (offset + frag_len > len) {
-			BUG_ON(frag != last_frag);
+			if (frag != last_frag) {
+				dev_kfree_skb_any(skb);
+				return -EIO;
+			}
 			frag_len = len - offset;
 		}
 		skb_copy_to_linear_data_offset(skb, offset,

@@ -844,9 +858,13 @@ static int macb_rx(struct macb *bp, int budget)
 
 		if (ctrl & MACB_BIT(RX_EOF)) {
 			int dropped;
-			BUG_ON(first_frag == -1);
+			if (first_frag == -1)
+				return -EIO;
 
 			dropped = macb_rx_frame(bp, first_frag, tail);
+			if (dropped < 0)
+				return dropped;
+
 			first_frag = -1;
 			if (!dropped) {
 				received++;

@@ -872,12 +890,22 @@ static int macb_poll(struct napi_struct *napi, int budget)
 	status = macb_readl(bp, RSR);
 	macb_writel(bp, RSR, status);
 
-	work_done = 0;
+	work_done = -EIO;
 
 	netdev_vdbg(bp->dev, "poll: status = %08lx, budget = %d\n",
-		   (unsigned long)status, budget);
+			(unsigned long)status, budget);
+
+	if (status & (MACB_BIT(OVR) | MACB_BIT(BNA)) ||
+	    !(status & MACB_BIT(REC))) {
+		netdev_err(bp->dev, "RX error, status = %02lx\n",
+			   (unsigned long)status);
+		goto rx_out;
+	}
 
 	work_done = bp->macbgem_ops.mog_rx(bp, budget);
+	if (work_done < 0)
+		goto rx_out;
+
 	if (work_done < budget) {
 		napi_complete(napi);
 

@@ -892,7 +920,23 @@ static int macb_poll(struct napi_struct *napi, int budget)
 		}
 	}
 
-	/* TODO: Handle errors */
+	return work_done;
+
+rx_out:
+	/* In case of error, disable RX and reset
+	 * the descriptor ring before re-enabling RX.
+	 */
+	macb_writel(bp, NCR, macb_readl(bp, NCR) & ~MACB_BIT(RE));
+
+	bp->macbgem_ops.mog_init_rx_rings(bp);
+	macb_writel(bp, RBQP, bp->rx_ring_dma);
+
+	/* Re-enable RX and get notified for new packets */
+	macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(RE));
+
+	napi_complete(napi);
+
+	macb_writel(bp, IER, MACB_RX_INT_FLAGS);
 
 	return work_done;
 }