xen/netback: free already allocated memory on failure in xen_netbk_get_requests
[ Upstream commit 4cc7c1cb7b11b6f3515bd9075527576a1eecc4aa ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index c71a731..4c41f5e 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -950,7 +950,7 @@
pending_idx = netbk->pending_ring[index];
page = xen_netbk_alloc_page(netbk, skb, pending_idx);
if (!page)
- return NULL;
+ goto err;
gop->source.u.ref = txp->gref;
gop->source.domid = vif->domid;
@@ -972,6 +972,17 @@
}
return gop;
+err:
+ /* Unwind, freeing all pages and sending error responses. */
+ while (i-- > start) {
+ xen_netbk_idx_release(netbk, frag_get_pending_idx(&frags[i]),
+ XEN_NETIF_RSP_ERROR);
+ }
+ /* The head too, if necessary. */
+ if (start)
+ xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR);
+
+ return NULL;
}
static int xen_netbk_tx_check_gop(struct xen_netbk *netbk,