[PATCH 4.4 078/146] drm/nouveau/fbcon: fix out-of-bounds memory accesses

Greg Kroah-Hartman
2016-07-25T22:39:22Z

From: Ben Skeggs <bskeggs@redhat.com>

commit f045f459d925138fe7d6193a8c86406bda7e49da upstream.

Reported by KASAN.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/nouveau/nouveau_fbcon.c | 1 +
drivers/gpu/drm/nouveau/nv04_fbcon.c | 7 ++-----
drivers/gpu/drm/nouveau/nv50_fbcon.c | 6 ++----
drivers/gpu/drm/nouveau/nvc0_fbcon.c | 6 ++----
4 files changed, 7 insertions(+), 13 deletions(-)

--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -557,6 +557,7 @@ nouveau_fbcon_init(struct drm_device *de
if (ret)
goto fini;

+ fbcon->helper.fbdev->pixmap.buf_align = 4;
return 0;

fini:
--- a/drivers/gpu/drm/nouveau/nv04_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nv04_fbcon.c
@@ -82,7 +82,6 @@ nv04_fbcon_imageblit(struct fb_info *inf
uint32_t fg;
uint32_t bg;
uint32_t dsize;
- uint32_t width;
uint32_t *data = (uint32_t *)image->data;
int ret;

@@ -93,9 +92,6 @@ nv04_fbcon_imageblit(struct fb_info *inf
if (ret)
return ret;

- width = ALIGN(image->width, 8);
- dsize = ALIGN(width * image->height, 32) >> 5;
-
if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
fg = ((uint32_t *) info->pseudo_palette)[image->fg_color];
@@ -111,10 +107,11 @@ nv04_fbcon_imageblit(struct fb_info *inf
((image->dx + image->width) & 0xffff));
OUT_RING(chan, bg);
OUT_RING(chan, fg);
- OUT_RING(chan, (image->height << 16) | width);
+ OUT_RING(chan, (image->height << 16) | image->width);
OUT_RING(chan, (image->height << 16) | image->width);
OUT_RING(chan, (image->dy << 16) | (image->dx & 0xffff));

+ dsize = ALIGN(image->width * image->height, 32) >> 5;
while (dsize) {
int iter_len = dsize > 128 ? 128 : dsize;

--- a/drivers/gpu/drm/nouveau/nv50_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nv50_fbcon.c
@@ -95,7 +95,7 @@ nv50_fbcon_imageblit(struct fb_info *inf
struct nouveau_fbdev *nfbdev = info->par;
struct nouveau_drm *drm = nouveau_drm(nfbdev->dev);
struct nouveau_channel *chan = drm->channel;
- uint32_t width, dwords, *data = (uint32_t *)image->data;
+ uint32_t dwords, *data = (uint32_t *)image->data;
uint32_t mask = ~(~0 >> (32 - info->var.bits_per_pixel));
uint32_t *palette = info->pseudo_palette;
int ret;
@@ -107,9 +107,6 @@ nv50_fbcon_imageblit(struct fb_info *inf
if (ret)
return ret;

- width = ALIGN(image->width, 32);
- dwords = (width * image->height) >> 5;
-
BEGIN_NV04(chan, NvSub2D, 0x0814, 2);
if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
@@ -128,6 +125,7 @@ nv50_fbcon_imageblit(struct fb_info *inf
OUT_RING(chan, 0);
OUT_RING(chan, image->dy);

+ dwords = ALIGN(image->width * image->height, 32) >> 5;
while (dwords) {
int push = dwords > 2047 ? 2047 : dwords;

--- a/drivers/gpu/drm/nouveau/nvc0_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nvc0_fbcon.c
@@ -95,7 +95,7 @@ nvc0_fbcon_imageblit(struct fb_info *inf
struct nouveau_fbdev *nfbdev = info->par;
struct nouveau_drm *drm = nouveau_drm(nfbdev->dev);
struct nouveau_channel *chan = drm->channel;
- uint32_t width, dwords, *data = (uint32_t *)image->data;
+ uint32_t dwords, *data = (uint32_t *)image->data;
uint32_t mask = ~(~0 >> (32 - info->var.bits_per_pixel));
uint32_t *palette = info->pseudo_palette;
int ret;
@@ -107,9 +107,6 @@ nvc0_fbcon_imageblit(struct fb_info *inf
if (ret)
return ret;

- width = ALIGN(image->width, 32);
- dwords = (width * image->height) >> 5;
-
BEGIN_NVC0(chan, NvSub2D, 0x0814, 2);
if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
@@ -128,6 +125,7 @@ nvc0_fbcon_imageblit(struct fb_info *inf
OUT_RING (chan, 0);
OUT_RING (chan, image->dy);

+ dwords = ALIGN(image->width * image->height, 32) >> 5;
while (dwords) {
int push = dwords > 2047 ? 2047 : dwords;