[PATCH 6.18 462/752] ASoC: SOF: ipc4-topology: Correct the allocation size for bytes controls

Sasha Levin
2026-02-28T17:54:38Z

From: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

[ Upstream commit a653820700b81c9e6f05ac23b7969ecec1a18e85 ]

The size of the data behind of scontrol->ipc_control_data for bytes
controls is:
[1] sizeof(struct sof_ipc4_control_data) + // kernel only struct
[2] sizeof(struct sof_abi_hdr)) + payload

The max_size specifies the size of [2] and it is coming from topology.

Change the function to take this into account and allocate adequate amount
of memory behind scontrol->ipc_control_data.

With the change we will allocate [1] amount more memory to be able to hold
the full size of data.

Fixes: a382082ff74b ("ASoC: SOF: ipc4-topology: Add support for TPLG_CTL_BYTES")
Cc: stable@vger.kernel.org
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://patch.msgid.link/20251217143945.2667-3-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/soc/sof/ipc4-topology.c | 35 +++++++++++++++++++++++++++--------
1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/sound/soc/sof/ipc4-topology.c b/sound/soc/sof/ipc4-topology.c
index 32b628e2fe29b..5ca995acaba2e 100644
--- a/sound/soc/sof/ipc4-topology.c
+++ b/sound/soc/sof/ipc4-topology.c
@@ -2861,22 +2861,41 @@ static int sof_ipc4_control_load_bytes(struct snd_sof_dev *sdev, struct snd_sof_
struct sof_ipc4_msg *msg;
int ret;

- if (scontrol->max_size < (sizeof(*control_data) + sizeof(struct sof_abi_hdr))) {
- dev_err(sdev->dev, "insufficient size for a bytes control %s: %zu.\n",
+ /*
+ * The max_size is coming from topology and indicates the maximum size
+ * of sof_abi_hdr plus the payload, which excludes the local only
+ * 'struct sof_ipc4_control_data'
+ */
+ if (scontrol->max_size < sizeof(struct sof_abi_hdr)) {
+ dev_err(sdev->dev,
+ "insufficient maximum size for a bytes control %s: %zu.\n",
scontrol->name, scontrol->max_size);
return -EINVAL;
}

- if (scontrol->priv_size > scontrol->max_size - sizeof(*control_data)) {
- dev_err(sdev->dev, "scontrol %s bytes data size %zu exceeds max %zu.\n",
- scontrol->name, scontrol->priv_size,
- scontrol->max_size - sizeof(*control_data));
+ if (scontrol->priv_size > scontrol->max_size) {
+ dev_err(sdev->dev,
+ "bytes control %s initial data size %zu exceeds max %zu.\n",
+ scontrol->name, scontrol->priv_size, scontrol->max_size);
+ return -EINVAL;
+ }
+
+ if (scontrol->priv_size < sizeof(struct sof_abi_hdr)) {
+ dev_err(sdev->dev,
+ "bytes control %s initial data size %zu is insufficient.\n",
+ scontrol->name, scontrol->priv_size);
return -EINVAL;
}

- scontrol->size = sizeof(struct sof_ipc4_control_data) + scontrol->priv_size;
+ /*
+ * The used size behind the cdata pointer, which can be smaller than
+ * the maximum size
+ */
+ scontrol->size = sizeof(*control_data) + scontrol->priv_size;

- scontrol->ipc_control_data = kzalloc(scontrol->max_size, GFP_KERNEL);
+ /* Allocate the cdata: local struct size + maximum payload size */
+ scontrol->ipc_control_data = kzalloc(sizeof(*control_data) + scontrol->max_size,
+ GFP_KERNEL);
if (!scontrol->ipc_control_data)
return -ENOMEM;

--
2.51.0