[PATCH v2] drm/bridge: sii902x: validate I2S data lane values

[PATCH v2] drm/bridge: sii902x: validate I2S data lane values

[Pengpeng Hou]

The sil,i2s-data-lanes property reader bounds the number of entries, but
does not bound each entry's value. Those values index the four-entry
i2s_lane_id table when the audio FIFO sequence is built.

Reject unsupported lane values before indexing that table. Report the
property name and invalid value with dev_err_probe() so the diagnostic
identifies the faulty configuration.

The issue was found by our static-analysis tool.

Fixes: ff5781634c41 ("drm/bridge: sii902x: Implement HDMI audio support")
Assisted-by: gpt 5
Signed-off-by: Pengpeng Hou <hppiscas@163.com>
---
Changes since v1:
https://lore.kernel.org/all/2026063007056160.5-ccfa108-0046-drm-bridge-sii902x-validate-pengpeng@iscas.ac.cn/
Use dev_err_probe() and identify sil,i2s-data-lanes in the diagnostic,
as Luca requested; add the verified introducing Fixes tag.

 drivers/gpu/drm/bridge/sii902x.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 9aac44ed5b67..48058029fdfc 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -890,9 +890,15 @@ static int sii902x_audio_codec_init(struct sii902x *sii902x,
 	}
 	codec_data.max_i2s_channels = 2 * num_lanes;
 
-	for (i = 0; i < num_lanes; i++)
+	for (i = 0; i < num_lanes; i++) {
+		if (lanes[i] >= ARRAY_SIZE(i2s_lane_id))
+			return dev_err_probe(dev, -EINVAL,
+					     "invalid sil,i2s-data-lanes value %u\n",
+					     lanes[i]);
+
 		sii902x->audio.i2s_fifo_sequence[i] |= audio_fifo_id[i] |
 			i2s_lane_id[lanes[i]] |	SII902X_TPI_I2S_FIFO_ENABLE;
+	}
 
 	sii902x->audio.mclk = devm_clk_get_optional(dev, "mclk");
 	if (IS_ERR(sii902x->audio.mclk)) {

base-commit: 518e5b794c06c0f0eb40df3e202274a66202c137
-- 
2.50.1 (Apple Git-155)