[PATCH 1/1] i3c: master: svc: return error when read length bigger than 255

[Frank Li]

RDTERM in MCTRL is 8 bits. Add a length check to prevent silent data errors
when the read length exceeds 255 bytes during each i3c_priv_xfer operation.

Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
 drivers/i3c/master/svc-i3c-master.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index bd10bb698da0f..181b56953fb28 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -1375,6 +1375,11 @@ static int svc_i3c_master_priv_xfers(struct i3c_dev_desc *dev,
 		cmd->len = xfers[i].len;
 		cmd->actual_len = xfers[i].rnw ? xfers[i].len : 0;
 		cmd->continued = (i + 1) < nxfers;
+
+		if (cmd->rnw && cmd->len > 255) {
+			dev_err(master->dev, "only support read less than 255 each xfer\n");
+			return -EINVAL;
+		}
 	}
 
 	mutex_lock(&master->lock);
-- 
2.34.1