Hi Ido,
On Mon, Mar 05, 2012 at 08:10:24PM +0200, Ido Yariv wrote:
> The cid or psm and the source address might not be enough to uniquely
> identify a global channel, especially when the source address is our
> own.
>
> For instance, when trying to communicate with two LE devices in master
> mode, data received from the both devices is sent to the same socket.
>
> Fix this by taking the destination address into account when choosing
> the socket.
>
> Signed-off-by: Ido Yariv <ido@xxxxxxxxxx>
> Signed-off-by: Arik Nemtsov <arik@xxxxxxxxxx>
> ---
> Note: Only the change done to l2cap_global_chan_by_scid was tested.
>
> net/bluetooth/l2cap_core.c | 48 +++++++++++++++++++++++++++++++++-----------
> 1 files changed, 36 insertions(+), 12 deletions(-)
>
> diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> index 0b1aabf..6491503 100644
> --- a/net/bluetooth/l2cap_core.c
> +++ b/net/bluetooth/l2cap_core.c
> @@ -831,10 +831,12 @@ static void l2cap_conn_start(struct l2cap_conn *conn)
> mutex_unlock(&conn->chan_lock);
> }
>
> -/* Find socket with cid and source bdaddr.
> +/* Find socket with cid and source/destination bdaddrs.
> * Returns closest match, locked.
> */
> -static struct l2cap_chan *l2cap_global_chan_by_scid(int state, __le16 cid, bdaddr_t *src)
> +static struct l2cap_chan *l2cap_global_chan_by_scid(int state, __le16 cid,
> + bdaddr_t *src,
> + bdaddr_t *dst)
> {
> struct l2cap_chan *c, *c1 = NULL;
>
> @@ -847,14 +849,24 @@ static struct l2cap_chan *l2cap_global_chan_by_scid(int state, __le16 cid, bdadd
> continue;
>
> if (c->scid == cid) {
> + int src_match, dst_match;
> + int src_any, dst_any;
> +
> + src_match = !bacmp(&bt_sk(sk)->src, src);
> + dst_match = !bacmp(&bt_sk(sk)->dst, dst);
> + src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
> + dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
This may be not efficient to use extensive memcmp operations every time
before they can be actually used.
> +
> /* Exact match. */
> - if (!bacmp(&bt_sk(sk)->src, src)) {
> + if (src_match && dst_match) {
> read_unlock(&chan_list_lock);
> return c;
> }
at least src_any and dst_any may be put here. Maybe you could improve it
even more.
>
> /* Closest match */
> - if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
> + if ((src_match && dst_any) ||
> + (src_any && dst_match) ||
> + (src_any && dst_any))
> c1 = c;
> }
> }
> @@ -873,7 +885,7 @@ static void l2cap_le_conn_ready(struct l2cap_conn *conn)
>
> /* Check if we have socket listening on cid */
> pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_LE_DATA,
> - conn->src);
> + conn->src, conn->dst);
> if (!pchan)
> return;
>
> @@ -1101,10 +1113,12 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon, u8 status)
>
> /* ---- Socket interface ---- */
>
> -/* Find socket with psm and source bdaddr.
> +/* Find socket with psm and source/destination bdaddrs.
> * Returns closest match.
> */
> -static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, bdaddr_t *src)
> +static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
> + bdaddr_t *src,
> + bdaddr_t *dst)
> {
> struct l2cap_chan *c, *c1 = NULL;
>
> @@ -1117,14 +1131,24 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, bdaddr
> continue;
>
> if (c->psm == psm) {
> + int src_match, dst_match;
> + int src_any, dst_any;
> +
> + src_match = !bacmp(&bt_sk(sk)->src, src);
> + dst_match = !bacmp(&bt_sk(sk)->dst, dst);
> + src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
> + dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
Same here.
Best regards
Andrei Emeltchenko
> +
> /* Exact match. */
> - if (!bacmp(&bt_sk(sk)->src, src)) {
> + if (src_match && dst_match) {
> read_unlock(&chan_list_lock);
> return c;
> }
>
> /* Closest match */
> - if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
> + if ((src_match && dst_any) ||
> + (src_any && dst_match) ||
> + (src_any && dst_any))
> c1 = c;
> }
Best regards
Andrei Emeltchenko
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