[PATCH] drm/edid: fix info leak when failing to get panel id

From: Johan Hovold
Date: Thu Mar 02 2023 - 02:49:06 EST


Make sure to clear the transfer buffer before fetching the EDID to
avoid leaking slab data to the logs on errors that leave the buffer
unchanged.

Fixes: 69c7717c20cc ("drm/edid: Dump the EDID when drm_edid_get_panel_id() has an error")
Cc: stable@xxxxxxxxxxxxxxx # 6.2
Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
drivers/gpu/drm/drm_edid.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 3841aba17abd..8707fe72a028 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -2797,7 +2797,7 @@ u32 drm_edid_get_panel_id(struct i2c_adapter *adapter)
* the EDID then we'll just return 0.
*/

- base_block = kmalloc(EDID_LENGTH, GFP_KERNEL);
+ base_block = kzalloc(EDID_LENGTH, GFP_KERNEL);
if (!base_block)
return 0;

--
2.39.2