From: Jeremy Kerr jk@codeconstruct.com.au
[ Upstream commit 1394c1dec1c619a46867ed32791a29695372bff8 ]
If we're fragmenting on local output, the original packet may contain ext data for the MCTP flows. We'll want this in the resulting fragment skbs too.
So, do a skb_ext_copy() in the fragmentation path, and implement the MCTP-specific parts of an ext copy operation.
Fixes: 67737c457281 ("mctp: Pass flow data & flow release events to drivers") Reported-by: Jian Zhang zhangjian.3032@bytedance.com Signed-off-by: Jeremy Kerr jk@codeconstruct.com.au Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/skbuff.c | 8 ++++++++ net/mctp/route.c | 3 +++ 2 files changed, 11 insertions(+)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index edbbef563d4d9..71dee435d549d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -6736,6 +6736,14 @@ static struct skb_ext *skb_ext_maybe_cow(struct skb_ext *old, for (i = 0; i < sp->len; i++) xfrm_state_hold(sp->xvec[i]); } +#endif +#ifdef CONFIG_MCTP_FLOWS + if (old_active & (1 << SKB_EXT_MCTP)) { + struct mctp_flow *flow = skb_ext_get_ptr(old, SKB_EXT_MCTP); + + if (flow->key) + refcount_inc(&flow->key->refs); + } #endif __skb_ext_put(old); return new; diff --git a/net/mctp/route.c b/net/mctp/route.c index ceee44ea09d97..01c530dbc1a65 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -843,6 +843,9 @@ static int mctp_do_fragment_route(struct mctp_route *rt, struct sk_buff *skb, /* copy message payload */ skb_copy_bits(skb, pos, skb_transport_header(skb2), size);
+ /* we need to copy the extensions, for MCTP flow data */ + skb_ext_copy(skb2, skb); + /* do route */ rc = rt->output(rt, skb2); if (rc)