[PATCH 3.4 20/23] drm/radeon: avoid leaking edid data

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alex Deucher <alexander.deucher@amd.com>

commit 0ac66effe7fcdee55bda6d5d10d3372c95a41920 upstream.

In some cases we fetch the edid in the detect() callback
in order to determine what sort of monitor is connected.
If that happens, don't fetch the edid again in the get_modes()
callback or we will leak the edid.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/radeon/radeon_display.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -709,6 +709,10 @@ int radeon_ddc_get_modes(struct radeon_c
 	struct radeon_device *rdev = dev->dev_private;
 	int ret = 0;
 
+	/* don't leak the edid if we already fetched it in detect() */
+	if (radeon_connector->edid)
+		goto got_edid;
+
 	/* on hw with routers, select right port */
 	if (radeon_connector->router.ddc_valid)
 		radeon_router_select_ddc_port(radeon_connector);
@@ -748,6 +752,7 @@ int radeon_ddc_get_modes(struct radeon_c
 			radeon_connector->edid = radeon_bios_get_hardcoded_edid(rdev);
 	}
 	if (radeon_connector->edid) {
+got_edid:
 		drm_mode_connector_update_edid_property(&radeon_connector->base, radeon_connector->edid);
 		ret = drm_add_edid_modes(&radeon_connector->base, radeon_connector->edid);
 		drm_edid_to_eld(&radeon_connector->base, radeon_connector->edid);