soundwire: fix port_ready[] dynamic allocation in mipi_disco
The existing code allocates memory for the total number of ports.
This only works if the ports are contiguous, but will break if e.g. a
Devices uses port0, 1, and 14. The port_ready[] array would contain 3
elements, which would lead to an out-of-bounds access. Conversely in
other cases, the wrong port index would be used leading to timeouts on
prepare.
This can be fixed by allocating for the worst-case of 15
ports (DP0..DP14). In addition since the number is now fixed, we can
use an array instead of a dynamic allocation.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Link: https://lore.kernel.org/r/20200831134318.11443-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c
index 0839445..a762ee2 100644
--- a/drivers/soundwire/slave.c
+++ b/drivers/soundwire/slave.c
@@ -25,6 +25,7 @@ static int sdw_slave_add(struct sdw_bus *bus,
{
struct sdw_slave *slave;
int ret;
+ int i;
slave = kzalloc(sizeof(*slave), GFP_KERNEL);
if (!slave)
@@ -58,6 +59,9 @@ static int sdw_slave_add(struct sdw_bus *bus,
init_completion(&slave->probe_complete);
slave->probed = false;
+ for (i = 0; i < SDW_MAX_PORTS; i++)
+ init_completion(&slave->port_ready[i]);
+
mutex_lock(&bus->bus_lock);
list_add_tail(&slave->node, &bus->slaves);
mutex_unlock(&bus->bus_lock);