[BlueZ,v5] a2dp: Fix crash when SEP codec has not been initialized

["Frédéric Danis" <frederic.danis@collabora.com>]

If SEP has not been properly discovered avdtp_get_codec may return NULL
thus causing crashes such as when running AVRCP/TG/VLH/BI-01-C after
AVRCP/TG/RCR/BV-04-C.

Prevent remote endpoint registration if its codec is not available.

Remove queue_isempty check from store_remote_seps since that prevents
cleaning up if no seps could be registered.
---
v5: fix avdtp_get_codec() check

 profiles/audio/a2dp.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
index c3ac432a7..21b3faa47 100644
--- a/profiles/audio/a2dp.c
+++ b/profiles/audio/a2dp.c
@@ -829,9 +829,6 @@ static void store_remote_seps(struct a2dp_channel *chan)
 	char *data;
 	gsize length = 0;
 
-	if (queue_isempty(chan->seps))
-		return;
-
 	ba2str(device_get_address(device), dst_addr);
 
 	snprintf(filename, PATH_MAX, STORAGEDIR "/%s/cache/%s",
@@ -2074,6 +2071,11 @@ static struct a2dp_remote_sep *register_remote_sep(void *data, void *user_data)
 	if (sep)
 		return sep;
 
+	if (!avdtp_get_codec(rsep)) {
+		error("Unable to get remote sep codec");
+		return NULL;
+	}
+
 	sep = new0(struct a2dp_remote_sep, 1);
 	sep->chan = chan;
 	sep->sep = rsep;
@@ -2148,6 +2150,7 @@ static void load_remote_sep(struct a2dp_channel *chan, GKeyFile *key_file,
 	struct avdtp_remote_sep *rsep;
 	uint8_t lseid, rseid;
 	char *value;
+	bool update = false;
 
 	if (!seids)
 		return;
@@ -2206,10 +2209,19 @@ static void load_remote_sep(struct a2dp_channel *chan, GKeyFile *key_file,
 		}
 
 		sep = register_remote_sep(rsep, chan);
-		if (sep)
-			sep->from_cache = true;
+		if (!sep) {
+			avdtp_unregister_remote_sep(chan->session, rsep);
+			update = true;
+			continue;
+		}
+
+		sep->from_cache = true;
 	}
 
+	/* Update cache */
+	if (update)
+		store_remote_seps(chan);
+
 	value = g_key_file_get_string(key_file, "Endpoints", "LastUsed", NULL);
 	if (!value)
 		return;
-- 
2.25.1