Merge branch 'field-zeroing' into for-linus

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 7c0fab1efb2e..e8387cb95d7f 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -872,8 +872,13 @@ static void hid_output_field(struct hid_field *field, __u8 *data)
 	unsigned count = field->report_count;
 	unsigned offset = field->report_offset;
 	unsigned size = field->report_size;
+	unsigned bitsused = offset + count * size;
 	unsigned n;
 
+	/* make sure the unused bits in the last byte are zeros */
+	if (count > 0 && size > 0 && (bitsused % 8) != 0)
+		data[(bitsused-1)/8] &= (1 << (bitsused % 8)) - 1;
+
 	for (n = 0; n < count; n++) {
 		if (field->logical_minimum < 0)	/* signed values */
 			implement(data, offset + n * size, size, s32ton(field->value[n], size));