Commit 61e71022 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

mptcp: do not warn on bad input from the network 

warn_bad_map() produces a kernel WARN on bad input coming
from the network. Use pr_debug() to avoid spamming the system
log.

Additionally, when the right bound check fails, warn_bad_map() reports
the wrong ssn value, let's fix it.

Fixes: 648ef4b8 ("mptcp: Implement MPTCP receive path")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/107


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 99d1055c

net/mptcp/subflow.c

+5 −5
Original line number Diff line number Diff line
@@ -784,9 +784,9 @@ static u64 expand_seq(u64 old_seq, u16 old_data_len, u64 seq) 
	return seq | ((old_seq + old_data_len + 1) & GENMASK_ULL(63, 32));

}



static void warn_bad_map(struct mptcp_subflow_context *subflow, u32 ssn)

static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn)

{

	WARN_ONCE(1, "Bad mapping: ssn=%d map_seq=%d map_data_len=%d",

	pr_debug("Bad mapping: ssn=%d map_seq=%d map_data_len=%d",

		 ssn, subflow->map_subflow_seq, subflow->map_data_len);

}
@@ -812,13 +812,13 @@ static bool validate_mapping(struct sock *ssk, struct sk_buff *skb) 
		/* Mapping covers data later in the subflow stream,

		 * currently unsupported.

		 */

		warn_bad_map(subflow, ssn);

		dbg_bad_map(subflow, ssn);

		return false;

	}

	if (unlikely(!before(ssn, subflow->map_subflow_seq +

				  subflow->map_data_len))) {

		/* Mapping does covers past subflow data, invalid */

		warn_bad_map(subflow, ssn + skb->len);

		dbg_bad_map(subflow, ssn);

		return false;

	}

	return true;