diff options
| author | Mat Martineau <mathew.j.martineau@linux.intel.com> | 2020-09-29 15:08:20 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-09-29 18:15:46 -0700 |
| commit | 1a49b2c2a501467587504e75bd049d43af38b692 (patch) | |
| tree | 59f8d418675ec25404f4504dbad9b71c8e253b43 /net/mptcp/subflow.c | |
| parent | 917944da3bfc7cb5ac3af26725af3371d3a12db0 (diff) | |
mptcp: Handle incoming 32-bit DATA_FIN values
The peer may send a DATA_FIN mapping with either a 32-bit or 64-bit
sequence number. When a 32-bit sequence number is received for the
DATA_FIN, it must be expanded to 64 bits before comparing it to the
last acked sequence number. This expansion was missing.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/93
Fixes: 3721b9b64676 ("mptcp: Track received DATA_FIN sequence number and add related helpers")
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp/subflow.c')
| -rw-r--r-- | net/mptcp/subflow.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 8cbeb68f3775..5f2fa935022d 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -731,7 +731,8 @@ static enum mapping_status get_mapping_status(struct sock *ssk, if (mpext->data_fin == 1) { if (data_len == 1) { - bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq); + bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq, + mpext->dsn64); pr_debug("DATA_FIN with no payload seq=%llu", mpext->data_seq); if (subflow->map_valid) { /* A DATA_FIN might arrive in a DSS @@ -748,8 +749,17 @@ static enum mapping_status get_mapping_status(struct sock *ssk, return MAPPING_DATA_FIN; } } else { - mptcp_update_rcv_data_fin(msk, mpext->data_seq + data_len); - pr_debug("DATA_FIN with mapping seq=%llu", mpext->data_seq + data_len); + u64 data_fin_seq = mpext->data_seq + data_len; + + /* If mpext->data_seq is a 32-bit value, data_fin_seq + * must also be limited to 32 bits. + */ + if (!mpext->dsn64) + data_fin_seq &= GENMASK_ULL(31, 0); + + mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); + pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", + data_fin_seq, mpext->dsn64); } /* Adjust for DATA_FIN using 1 byte of sequence space */ |