From: Archie Pusaka <[email protected]>
There is a possibility where BlueZ initiate an A2DP connection just
around the same time as the peripheral also initiate it.
One scenario is the peripheral initiate the connection first, so
confirm_cb() on /profiles/audio/a2dp.c is called. However, while we
are waiting for the authentication step, BlueZ initiate a connection
to the peripheral, therefore a2dp_sink_connect() is called, which
from there a2dp_avdtp_get() is called.
If this happens: When calling confirm_cb(), chan for the
corresponding device is created.
Then when calling a2dp_avdtp_get(), chan will be found as it is
created in confirm_cb(), and the value of chan->io is not NULL.
However, a NULL is supplied instead to create a new session and
assigned to chan->session.
Then when calling connect_cb(), chan->session will NOT be NULL, as
it is assigned in a2dp_avdtp_get(). Nevertheless, chan->session is
always assigned a new value.
These cause failure in connection.
Therefore, fixing this by supplying the value of chan->io inside
a2dp_avdtp_get() (it's going to be NULL on the normal case so it is
fine), and check whether chan->session already assigned inside
connect_cb().
---
profiles/audio/a2dp.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
index e8262cdfe..a5590b24c 100644
--- a/profiles/audio/a2dp.c
+++ b/profiles/audio/a2dp.c
@@ -2118,7 +2118,7 @@ struct avdtp *a2dp_avdtp_get(struct btd_device *device)
return NULL;
found:
- chan->session = avdtp_new(NULL, device, server->seps);
+ chan->session = avdtp_new(chan->io, device, server->seps);
if (!chan->session) {
channel_remove(chan);
return NULL;
@@ -2136,10 +2136,13 @@ static void connect_cb(GIOChannel *io, GError *err, gpointer user_data)
goto fail;
}
- chan->session = avdtp_new(chan->io, chan->device, chan->server->seps);
if (!chan->session) {
- error("Unable to create AVDTP session");
- goto fail;
+ chan->session = avdtp_new(chan->io, chan->device,
+ chan->server->seps);
+ if (!chan->session) {
+ error("Unable to create AVDTP session");
+ goto fail;
+ }
}
g_io_channel_unref(chan->io);
--
2.25.1.481.gfbce0eb801-goog
Hi Archie,
On Wed, Mar 11, 2020 at 10:55 PM Archie Pusaka <[email protected]> wrote:
>
> From: Archie Pusaka <[email protected]>
>
> There is a possibility where BlueZ initiate an A2DP connection just
> around the same time as the peripheral also initiate it.
>
> One scenario is the peripheral initiate the connection first, so
> confirm_cb() on /profiles/audio/a2dp.c is called. However, while we
> are waiting for the authentication step, BlueZ initiate a connection
> to the peripheral, therefore a2dp_sink_connect() is called, which
> from there a2dp_avdtp_get() is called.
>
> If this happens: When calling confirm_cb(), chan for the
> corresponding device is created.
>
> Then when calling a2dp_avdtp_get(), chan will be found as it is
> created in confirm_cb(), and the value of chan->io is not NULL.
> However, a NULL is supplied instead to create a new session and
> assigned to chan->session.
>
> Then when calling connect_cb(), chan->session will NOT be NULL, as
> it is assigned in a2dp_avdtp_get(). Nevertheless, chan->session is
> always assigned a new value.
>
> These cause failure in connection.
>
> Therefore, fixing this by supplying the value of chan->io inside
> a2dp_avdtp_get() (it's going to be NULL on the normal case so it is
> fine), and check whether chan->session already assigned inside
> connect_cb().
> ---
>
> profiles/audio/a2dp.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
> index e8262cdfe..a5590b24c 100644
> --- a/profiles/audio/a2dp.c
> +++ b/profiles/audio/a2dp.c
> @@ -2118,7 +2118,7 @@ struct avdtp *a2dp_avdtp_get(struct btd_device *device)
> return NULL;
>
> found:
> - chan->session = avdtp_new(NULL, device, server->seps);
> + chan->session = avdtp_new(chan->io, device, server->seps);
> if (!chan->session) {
> channel_remove(chan);
> return NULL;
> @@ -2136,10 +2136,13 @@ static void connect_cb(GIOChannel *io, GError *err, gpointer user_data)
> goto fail;
> }
>
> - chan->session = avdtp_new(chan->io, chan->device, chan->server->seps);
> if (!chan->session) {
> - error("Unable to create AVDTP session");
> - goto fail;
> + chan->session = avdtp_new(chan->io, chan->device,
> + chan->server->seps);
> + if (!chan->session) {
> + error("Unable to create AVDTP session");
> + goto fail;
> + }
> }
>
> g_io_channel_unref(chan->io);
> --
> 2.25.1.481.gfbce0eb801-goog
Applied, thanks.
--
Luiz Augusto von Dentz