From: Johan Hovold <johan+linaro@kernel.org>
Date: Thu, 2 Mar 2023 08:47:04 +0100
Subject: [PATCH] drm/edid: fix info leak when failing to get panel id
References: bsc#1012628
Patch-mainline: 6.2.8
Git-commit: 4d8457fe0eb9c80ff7795cf8a30962128b71d853

commit 4d8457fe0eb9c80ff7795cf8a30962128b71d853 upstream.

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@vger.kernel.org	# 6.2
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230302074704.11371-1-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 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 b94adb9b..0116c947 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;
 
-- 
2.35.3