From 1394c1dec1c619a46867ed32791a29695372bff8 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Mon, 19 Feb 2024 17:51:54 +0800 Subject: [PATCH] net: mctp: copy skb ext data when fragmenting 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 Signed-off-by: Jeremy Kerr Signed-off-by: Paolo Abeni --- 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 b9de3ee65ae64..1f918e602bc4f 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -6849,6 +6849,14 @@ 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 28648a7ec8666..34e5131135093 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -905,6 +905,9 @@ 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) -- 2.30.2