xen/netback: Reset nr_frags before freeing skb

At this point nr_frags has been incremented but the frag does not yet have a page assigned so freeing the skb results in a crash. Reset nr_frags before freeing the skb to prevent this. Signed-off-by: Ross Lagerwall <[email protected]> Signed-off-by: David S. Miller <[email protected]>
boxfire · Aug 9, 2019 · 3a0233d · 3a0233d
1 parent 891584f
commit 3a0233d
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
@@ -925,6 +925,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
 			skb_shinfo(skb)->nr_frags = MAX_SKB_FRAGS;
 			nskb = xenvif_alloc_skb(0);
 			if (unlikely(nskb == NULL)) {
+				skb_shinfo(skb)->nr_frags = 0;
 				kfree_skb(skb);
 				xenvif_tx_err(queue, &txreq, extra_count, idx);
 				if (net_ratelimit())
@@ -940,6 +941,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
 
 			if (xenvif_set_skb_gso(queue->vif, skb, gso)) {
 				/* Failure in xenvif_set_skb_gso is fatal. */
+				skb_shinfo(skb)->nr_frags = 0;
 				kfree_skb(skb);
 				kfree_skb(nskb);
 				break;