4.20-stable review patch. If anyone has any objections, please let me know.
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From: Willem de Bruijn willemb@google.com
[ Upstream commit 0f149c9fec3cd720628ecde83bfc6f64c1e7dcb6 ]
Failure __ip_append_data triggers udp_flush_pending_frames, but these tests happen later. The skb must be freed directly.
Fixes: bec1f6f697362 ("udp: generate gso with UDP_SEGMENT") Reported-by: Eric Dumazet edumazet@google.com Signed-off-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/udp.c | 16 ++++++++++++---- net/ipv6/udp.c | 16 ++++++++++++---- 2 files changed, 24 insertions(+), 8 deletions(-)
--- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -785,15 +785,23 @@ static int udp_send_skb(struct sk_buff * const int hlen = skb_network_header_len(skb) + sizeof(struct udphdr);
- if (hlen + cork->gso_size > cork->fragsize) + if (hlen + cork->gso_size > cork->fragsize) { + kfree_skb(skb); return -EINVAL; - if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) + } + if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) { + kfree_skb(skb); return -EINVAL; - if (sk->sk_no_check_tx) + } + if (sk->sk_no_check_tx) { + kfree_skb(skb); return -EINVAL; + } if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite || - dst_xfrm(skb_dst(skb))) + dst_xfrm(skb_dst(skb))) { + kfree_skb(skb); return -EIO; + }
skb_shinfo(skb)->gso_size = cork->gso_size; skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4; --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1056,15 +1056,23 @@ static int udp_v6_send_skb(struct sk_buf const int hlen = skb_network_header_len(skb) + sizeof(struct udphdr);
- if (hlen + cork->gso_size > cork->fragsize) + if (hlen + cork->gso_size > cork->fragsize) { + kfree_skb(skb); return -EINVAL; - if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) + } + if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) { + kfree_skb(skb); return -EINVAL; - if (udp_sk(sk)->no_check6_tx) + } + if (udp_sk(sk)->no_check6_tx) { + kfree_skb(skb); return -EINVAL; + } if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite || - dst_xfrm(skb_dst(skb))) + dst_xfrm(skb_dst(skb))) { + kfree_skb(skb); return -EIO; + }
skb_shinfo(skb)->gso_size = cork->gso_size; skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;