diff options
| author | Juergen Gross <jgross@suse.com> | 2018-09-11 09:04:48 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-29 03:08:51 -0700 |
| commit | bd1468048aa3e2af865da92990539946d4483989 (patch) | |
| tree | 96d38ac333bb80f0fc1dbff356bcdff02f64d354 | |
| parent | 39b38432c8ac6c084a8cadc3dba07c570ac2866b (diff) | |
xen/netfront: don't bug in case of too many frags
commit ad4f15dc2c70b1de5e0a64d27335962fbc9cf71c upstream.
Commit 57f230ab04d291 ("xen/netfront: raise max number of slots in
xennet_get_responses()") raised the max number of allowed slots by one.
This seems to be problematic in some configurations with netback using
a larger MAX_SKB_FRAGS value (e.g. old Linux kernel with MAX_SKB_FRAGS
defined as 18 instead of nowadays 17).
Instead of BUG_ON() in this case just fall back to retransmission.
Fixes: 57f230ab04d291 ("xen/netfront: raise max number of slots in xennet_get_responses()")
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/xen-netfront.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 3270b4333668..0a4bd73caae5 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -892,7 +892,11 @@ static RING_IDX xennet_fill_frags(struct netfront_queue *queue, BUG_ON(pull_to <= skb_headlen(skb)); __pskb_pull_tail(skb, pull_to - skb_headlen(skb)); } - BUG_ON(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS); + if (unlikely(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS)) { + queue->rx.rsp_cons = ++cons; + kfree_skb(nskb); + return ~0U; + } skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, skb_frag_page(nfrag), @@ -1029,6 +1033,8 @@ err: skb->len += rx->status; i = xennet_fill_frags(queue, skb, &tmpq); + if (unlikely(i == ~0U)) + goto err; if (rx->flags & XEN_NETRXF_csum_blank) skb->ip_summed = CHECKSUM_PARTIAL; |