espintcp: count packets dropped in espintcp_rcv

Currently, espintcp_rcv drops packets silently, which makes debugging
issues difficult. Count packets as either XfrmInHdrError (when the
packet was too short or contained invalid data) or XfrmInError (for
other issues).

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/xfrm/espintcp.c b/net/xfrm/espintcp.c
index 0a91b07f2b43c68f78f85ed7b95ec884b199d4ff..827ccdf2db57f6b567a079c5ade39279061d84e4 100644 (file)
--- a/net/xfrm/espintcp.c
+++ b/net/xfrm/espintcp.c
@@ -15,6 +15,7 @@ static void handle_nonesp(struct espintcp_ctx *ctx, struct sk_buff *skb,
 {
        if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf ||
            !sk_rmem_schedule(sk, skb, skb->truesize)) {
+               XFRM_INC_STATS(sock_net(sk), LINUX_MIB_XFRMINERROR);
                kfree_skb(skb);
                return;
        }
@@ -59,6 +60,7 @@ static void espintcp_rcv(struct strparser *strp, struct sk_buff *skb)
 
                err = skb_copy_bits(skb, rxm->offset + 2, &data, 1);
                if (err < 0) {
+                       XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINHDRERROR);
                        kfree_skb(skb);
                        return;
                }
@@ -71,6 +73,7 @@ static void espintcp_rcv(struct strparser *strp, struct sk_buff *skb)
 
        /* drop other short messages */
        if (unlikely(len <= sizeof(nonesp_marker))) {
+               XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINHDRERROR);
                kfree_skb(skb);
                return;
        }
@@ -78,17 +81,20 @@ static void espintcp_rcv(struct strparser *strp, struct sk_buff *skb)
        err = skb_copy_bits(skb, rxm->offset + 2, &nonesp_marker,
                            sizeof(nonesp_marker));
        if (err < 0) {
+               XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINHDRERROR);
                kfree_skb(skb);
                return;
        }
 
        /* remove header, leave non-ESP marker/SPI */
        if (!__pskb_pull(skb, rxm->offset + 2)) {
+               XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINERROR);
                kfree_skb(skb);
                return;
        }
 
        if (pskb_trim(skb, rxm->full_len - 2) != 0) {
+               XFRM_INC_STATS(sock_net(strp->sk), LINUX_MIB_XFRMINERROR);
                kfree_skb(skb);
                return;
        }