[Intel-gfx] [PATCH] drm/i915: Free write_buf that we allocated with kzalloc.

[Rodrigo Vivi]

We use kzalloc to allocate the write_buf that we use for
i2c transfer on hdcp write. But it seems that we are forgetting
to free the memory that is not needed after i2c transfer is
completed.

Reported-by: Brian J Wood <brian.j.wood at intel.com>
Fixes: 2320175feb74 ("drm/i915: Implement HDCP for HDMI")
Cc: Ramalingam C <ramalingam.c at intel.com>
Cc: Sean Paul <seanpaul at chromium.org>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: <stable at vger.kernel.org> # v4.17+
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/intel_hdmi.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 8363fbd18ee8..a1799b5c12bb 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -943,8 +943,12 @@ static int intel_hdmi_hdcp_write(struct intel_digital_port *intel_dig_port,
 
 	ret = i2c_transfer(adapter, &msg, 1);
 	if (ret == 1)
-		return 0;
-	return ret >= 0 ? -EIO : ret;
+		ret = 0;
+	else if (ret >= 0)
+		ret = -EIO;
+
+	kfree(write_buf);
+	return ret;
 }
 
 static
-- 
2.17.1