| Message ID | 20190805153434.12144-1-ross.lagerwall@citrix.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 3a0233ddec554b886298de2428edb5c50a20e694 |
| Headers | show |
| Series | xen/netback: Reset nr_frags before freeing skb | expand |
From: Ross Lagerwall <ross.lagerwall@citrix.com> Date: Mon, 5 Aug 2019 16:34:34 +0100 > 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 <ross.lagerwall@citrix.com> Applied and queued up for -stable.
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 1d9940d4e8c7..c9262ffeefe4 100644 --- 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;
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 <ross.lagerwall@citrix.com> --- drivers/net/xen-netback/netback.c | 2 ++ 1 file changed, 2 insertions(+)