[PATCH 4.18 068/123] udl-kms: fix crash due to uninitialized memory

From: Greg Kroah-Hartman
Date: Mon Sep 03 2018 - 13:39:23 EST


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

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

From: Mikulas Patocka <mpatocka@xxxxxxxxxx>

commit 09a00abe3a9941c2715ca83eb88172cd2f54d8fd upstream.

We must use kzalloc when allocating the fb_deferred_io structure.
Otherwise, the field first_io is undefined and it causes a crash.

Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/udl/udl_fb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/udl/udl_fb.c
+++ b/drivers/gpu/drm/udl/udl_fb.c
@@ -221,7 +221,7 @@ static int udl_fb_open(struct fb_info *i

struct fb_deferred_io *fbdefio;

- fbdefio = kmalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);
+ fbdefio = kzalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);

if (fbdefio) {
fbdefio->delay = DL_DEFIO_WRITE_DELAY;