6.12-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Abeni pabeni@redhat.com
commit 56b824eb49d6258aa0bad09a406ceac3f643cdae upstream.
Currently the skb size after coalescing is only limited by the skb layout (the skb must not carry frag_list). A single coalesced skb covering several MSS can potentially fill completely the receive buffer. In such a case, the snd win will zero until the receive buffer will be empty again, affecting tput badly.
Fixes: 8268ed4c9d19 ("mptcp: introduce and use mptcp_try_coalesce()") Cc: stable@vger.kernel.org # please delay 2 weeks after 6.13-final release Signed-off-by: Paolo Abeni pabeni@redhat.com Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://patch.msgid.link/20241230-net-mptcp-rbuf-fixes-v1-3-8608af434ceb@ker... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/protocol.c | 1 + 1 file changed, 1 insertion(+)
--- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -136,6 +136,7 @@ static bool mptcp_try_coalesce(struct so int delta;
if (MPTCP_SKB_CB(from)->offset || + ((to->len + from->len) > (sk->sk_rcvbuf >> 3)) || !skb_try_coalesce(to, from, &fragstolen, &delta)) return false;