From: Ross Lagerwall <[email protected]> [ Upstream commit 3a0233ddec554b886298de2428edb5c50a20e694 ]
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]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/net/xen-netback/netback.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -927,6 +927,7 @@ static void xenvif_tx_build_gops(struct 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()) @@ -942,6 +943,7 @@ static void xenvif_tx_build_gops(struct 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;
