Hi Mat,
quoted hunk ↗ jump to hunk
When configuring an ERTM or streaming mode connection, remote devices
are expected to send an RFC option in a successful config response. A
misbehaving remote device might not send an RFC option, and the L2CAP
code should not access uninitialized data in this case.
Signed-off-by: Mat Martineau <redacted>
---
net/bluetooth/l2cap_core.c | 11 ++++++++++-
1 files changed, 10 insertions(+), 1 deletions(-)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 5ea94a1..45dd423 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -2152,7 +2152,7 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, voi
void *ptr = req->data;
int type, olen;
unsigned long val;
- struct l2cap_conf_rfc rfc;
+ struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
@@ -2271,6 +2271,15 @@ static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
}
}
+ /* Use sane default values in case a misbehaving remote device
+ * did not send an RFC option.
+ */
+ BT_ERR("Expected RFC option was not found, using defaults");
+ rfc.mode = chan->mode;
+ rfc.retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
+ rfc.monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
+ rfc.max_pdu_size = cpu_to_le16(chan->imtu);
I would actually put the BT_ERR afterwards the assignments separated
with an extra empty line, but that is just to make it a bit easier on
the eyes.
quoted hunk ↗ jump to hunk
+
done:
switch (rfc.mode) {
case L2CAP_MODE_ERTM:
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Regards
Marcel