From a01421e4484327fe44f8e126793ed5a48a221e24 Mon Sep 17 00:00:00 2001
From: Vlad Tsyrklevich <vlad@tsyrklevich.net>
Date: Fri, 11 Jan 2019 14:34:38 +0100
Subject: omap2fb: Fix stack memory disclosure
Git-commit: a01421e4484327fe44f8e126793ed5a48a221e24
Patch-mainline: v5.0-rc3
References: bsc#1120902
Using [1] for static analysis I found that the OMAPFB_QUERY_PLANE,
OMAPFB_GET_COLOR_KEY, OMAPFB_GET_DISPLAY_INFO, and OMAPFB_GET_VRAM_INFO
cases could all leak uninitialized stack memory--either due to
uninitialized padding or 'reserved' fields.
Fix them by clearing the shared union used to store copied out data.
[1] https://github.com/vlad902/kernel-uninitialized-memory-checker
Signed-off-by: Vlad Tsyrklevich <vlad@tsyrklevich.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Fixes: b39a982ddecf ("OMAP: DSS2: omapfb driver")
Cc: security@kernel.org
[b.zolnierkie: prefix patch subject with "omap2fb: "]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c b/drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c
index a3edb20ea4c3..a846d32ee653 100644
--- a/drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c
+++ b/drivers/video/fbdev/omap2/omapfb/omapfb-ioctl.c
@@ -609,6 +609,8 @@ int omapfb_ioctl(struct fb_info *fbi, unsigned int cmd, unsigned long arg)
int r = 0;
+ memset(&p, 0, sizeof(p));
+
switch (cmd) {
case OMAPFB_SYNC_GFX:
DBG("ioctl SYNC_GFX\n");
--
2.20.1