skbuff: Release nfct refcount on napi stolen or re-used skbs

commit 8550ff8d8c75416e984d9c4b082845e57e560984 upstream.

When multiple SKBs are merged to a new skb under napi GRO,
or SKB is re-used by napi, if nfct was set for them in the
driver, it will not be released while freeing their stolen
head state or on re-use.

Release nfct on napi's stolen or re-used SKBs, and
in gro_list_prepare, check conntrack metadata diff.

Fixes: 5c6b94604744 ("net/mlx5e: CT: Handle misses after executing CT action")
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/core/dev.c b/net/core/dev.c
index 8185966e0a37718ee99fcecb911d176ccff3c41f..a44d001237024966d1c38aab9b78e62843d27f20 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5870,6 +5870,18 @@ static struct list_head *gro_list_prepare(struct napi_struct *napi,
                        diffs = memcmp(skb_mac_header(p),
                                       skb_mac_header(skb),
                                       maclen);
+
+               diffs |= skb_get_nfct(p) ^ skb_get_nfct(skb);
+
+               if (!diffs) {
+                       struct tc_skb_ext *skb_ext = skb_ext_find(skb, TC_SKB_EXT);
+                       struct tc_skb_ext *p_ext = skb_ext_find(p, TC_SKB_EXT);
+
+                       diffs |= (!!p_ext) ^ (!!skb_ext);
+                       if (!diffs && unlikely(skb_ext))
+                               diffs |= p_ext->chain ^ skb_ext->chain;
+               }
+
                NAPI_GRO_CB(p)->same_flow = !diffs;
        }
 
@@ -6149,6 +6161,7 @@ static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
        skb_shinfo(skb)->gso_type = 0;
        skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
        skb_ext_reset(skb);
+       nf_reset_ct(skb);
 
        napi->skb = skb;
 }

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index d17b87aabc8b6345d8bb5253a2a447004942d742..2d27aae6d36ff9403ab521fe54bdb6e40e742ddd 100644 (file)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -659,6 +659,7 @@ fastpath:
 
 void skb_release_head_state(struct sk_buff *skb)
 {
+       nf_reset_ct(skb);
        skb_dst_drop(skb);
        if (skb->destructor) {
                WARN_ON(in_irq());