[PATCH BlueZ v1 1/1] shared/vcp: Fixed the crash observed with VOCS when pairing with LE Audio TWS earbuds

[Nitin Jadhav <nitin.jadhav@xxxxxxx>]

Root cause
- There are two types of database- Remote and Local (rdb and ldb).
- In client mode currently the code was written to access ldb.

Fix
- Correcting it, to access rdb has resolved the problem in VOCS.
- Same correction is done for VCS.

Reported-by: Pauli Virtanen <pav@xxxxxx>
---
 src/shared/vcp.c | 52 +++++++++++++++++++++++++++---------------------
 1 file changed, 29 insertions(+), 23 deletions(-)

diff --git a/src/shared/vcp.c b/src/shared/vcp.c
index 74bd01729..f30d7a533 100644
--- a/src/shared/vcp.c
+++ b/src/shared/vcp.c
@@ -973,7 +973,7 @@ static void vocs_voaodec_read(struct gatt_db_attribute *attrib,
 	struct bt_vocs *vocs = user_data;
 	struct iovec iov;
 
-	iov.iov_base = &vocs->vocs_ao_dec;
+	iov.iov_base = vocs->vocs_ao_dec;
 	iov.iov_len = strlen(vocs->vocs_ao_dec);
 
 	gatt_db_attribute_read_result(attrib, id, 0, iov.iov_base,
@@ -998,10 +998,12 @@ static struct bt_vcs *vcs_new(struct gatt_db *db, struct bt_vcp_db *vdb)
 
 	/* Populate DB with VCS attributes */
 	bt_uuid16_create(&uuid, VCS_UUID);
-	vcs->service = gatt_db_add_service(db, &uuid, true, 9);
+
+	vcs->service = gatt_db_add_service(db, &uuid, true, 10);
 	gatt_db_service_add_included(vcs->service, vdb->vocs->service);
 	gatt_db_service_set_active(vdb->vocs->service, true);
 
+
 	bt_uuid16_create(&uuid, VOL_STATE_CHRC_UUID);
 	vcs->vs = gatt_db_service_add_characteristic(vcs->service,
 					&uuid,
@@ -1385,11 +1387,12 @@ static void read_vocs_audio_location(struct bt_vcp *vcp, bool success,
 				     const uint8_t *value, uint16_t length,
 				     void *user_data)
 {
-	uint32_t *vocs_audio_loc;
-	struct iovec iov = {
-		.iov_base = (void *) value,
-		.iov_len = length,
-	};
+	uint32_t vocs_audio_loc;
+
+	if (!value) {
+		DBG(vcp, "Unable to get VOCS Audio Location");
+		return;
+	}
 
 	if (!success) {
 		DBG(vcp, "Unable to read VOCS Audio Location: error 0x%02x",
@@ -1397,26 +1400,25 @@ static void read_vocs_audio_location(struct bt_vcp *vcp, bool success,
 		return;
 	}
 
-	vocs_audio_loc = iov_pull_mem(&iov, sizeof(uint32_t));
-	if (!*vocs_audio_loc) {
-		DBG(vcp, "Unable to get VOCS Audio Location");
-		return;
-	}
+	memcpy(&vocs_audio_loc, value, length);
 
-	DBG(vcp, "VOCS Audio Loc:%x", *vocs_audio_loc);
+	DBG(vcp, "VOCS Audio Loc:%x", vocs_audio_loc);
 }
 
-
 static void read_vocs_audio_descriptor(struct bt_vcp *vcp, bool success,
 				       uint8_t att_ecode,
 				       const uint8_t *value, uint16_t length,
 				       void *user_data)
 {
 	char *vocs_ao_dec_r;
-	struct iovec iov = {
-		.iov_base = (void *) value,
-		.iov_len = length,
-	};
+
+	if (!value) {
+		DBG(vcp, "Unable to get VOCS Audio Descriptor");
+		return;
+	}
+
+	vocs_ao_dec_r = malloc(length+1);
+	memset(vocs_ao_dec_r, 0, length+1);
 
 	if (!success) {
 		DBG(vcp, "Unable to read VOCS Audio Descriptor: error 0x%02x",
@@ -1424,13 +1426,17 @@ static void read_vocs_audio_descriptor(struct bt_vcp *vcp, bool success,
 		return;
 	}
 
-	vocs_ao_dec_r = iov_pull_mem(&iov, length);
-	if (!*vocs_ao_dec_r) {
+	memcpy(vocs_ao_dec_r, value, length);
+
+	if (!vocs_ao_dec_r) {
 		DBG(vcp, "Unable to get VOCS Audio Descriptor");
 		return;
 	}
 
-	DBG(vcp, "VOCS Audio Descriptor:%s", *vocs_ao_dec_r);
+	DBG(vcp, "VOCS Audio Descriptor: %s", vocs_ao_dec_r);
+
+	free(vocs_ao_dec_r);
+	vocs_ao_dec_r = NULL;
 }
 
 static void vcp_pending_destroy(void *data)
@@ -1719,10 +1725,10 @@ bool bt_vcp_attach(struct bt_vcp *vcp, struct bt_gatt_client *client)
 		return false;
 
 	bt_uuid16_create(&uuid, VCS_UUID);
-	gatt_db_foreach_service(vcp->ldb->db, &uuid, foreach_vcs_service, vcp);
+	gatt_db_foreach_service(vcp->rdb->db, &uuid, foreach_vcs_service, vcp);
 
 	bt_uuid16_create(&uuid, VOL_OFFSET_CS_UUID);
-	gatt_db_foreach_service(vcp->ldb->db, &uuid, foreach_vocs_service, vcp);
+	gatt_db_foreach_service(vcp->rdb->db, &uuid, foreach_vocs_service, vcp);
 
 	return true;
 }
-- 
2.34.1