[PATCH 2/3] Input: synaptics-rmi4 - use the number of valid bytes read when updating the attn_data fields in F11 and F12

[Andrew Duggan]

Currently, rmi_f11_attention() and rmi_f12_attention() functions update
the attn_data data pointer and size based on the size of the expected
size of the attention data. However, if the actual valid data in the
attn buffer is less then the expected value then the updated data
pointer will point to memory beyond the end of the attn buffer. Using
the calculated valid_bytes instead will prevent this from happening.

Signed-off-by: Andrew Duggan <aduggan@xxxxxxxxxxxxx>
---
 drivers/input/rmi4/rmi_f11.c | 4 ++--
 drivers/input/rmi4/rmi_f12.c | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/input/rmi4/rmi_f11.c b/drivers/input/rmi4/rmi_f11.c
index f28a7158b2ef..26c239325f95 100644
--- a/drivers/input/rmi4/rmi_f11.c
+++ b/drivers/input/rmi4/rmi_f11.c
@@ -1284,8 +1284,8 @@ static irqreturn_t rmi_f11_attention(int irq, void *ctx)
 			valid_bytes = f11->sensor.attn_size;
 		memcpy(f11->sensor.data_pkt, drvdata->attn_data.data,
 			valid_bytes);
-		drvdata->attn_data.data += f11->sensor.attn_size;
-		drvdata->attn_data.size -= f11->sensor.attn_size;
+		drvdata->attn_data.data += valid_bytes;
+		drvdata->attn_data.size -= valid_bytes;
 	} else {
 		error = rmi_read_block(rmi_dev,
 				data_base_addr, f11->sensor.data_pkt,
diff --git a/drivers/input/rmi4/rmi_f12.c b/drivers/input/rmi4/rmi_f12.c
index 734077f2c40b..7e97944f7616 100644
--- a/drivers/input/rmi4/rmi_f12.c
+++ b/drivers/input/rmi4/rmi_f12.c
@@ -212,8 +212,8 @@ static irqreturn_t rmi_f12_attention(int irq, void *ctx)
 			valid_bytes = sensor->attn_size;
 		memcpy(sensor->data_pkt, drvdata->attn_data.data,
 			valid_bytes);
-		drvdata->attn_data.data += sensor->attn_size;
-		drvdata->attn_data.size -= sensor->attn_size;
+		drvdata->attn_data.data += valid_bytes;
+		drvdata->attn_data.size -= valid_bytes;
 	} else {
 		retval = rmi_read_block(rmi_dev, f12->data_addr,
 					sensor->data_pkt, sensor->pkt_size);
-- 
2.20.1