From 28668f43b8e421634e1623f72a879812288dd06b Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Thu, 28 Jul 2016 18:56:13 -0400 Subject: [PATCH] drm/nouveau/fbcon: fix font width not divisible by 8 The patch f045f459d925 ("drm/nouveau/fbcon: fix out-of-bounds memory accesses") tries to fix some out of memory accesses. Unfortunatelly, the patch breaks the display when using fonts with width that is not divisiable by 8. The monochrome bitmap for each character is stored in memory by lines from top to bottom. Each line is padded to a full byte. For example, for 22x11 font, each line is padded to 16 bits, so each character is consuming 44 bytes total, that is 11 32-bit words. The patch f045f459d925 changed the logic to "dsize = ALIGN(image->width * image->height, 32) >> 5", that is just 8 words - this is incorrect and it causes display corruption. This patch adds the necesary padding of lines to 8 bytes. This patch should be backported to stable kernels where f045f459d925 was backported. Signed-off-by: Mikulas Patocka Fixes: f045f459d925 ("drm/nouveau/fbcon: fix out-of-bounds memory accesses") Cc: stable@vger.kernel.org Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nv04_fbcon.c | 4 ++-- drivers/gpu/drm/nouveau/nv50_fbcon.c | 2 +- drivers/gpu/drm/nouveau/nvc0_fbcon.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nv04_fbcon.c b/drivers/gpu/drm/nouveau/nv04_fbcon.c index 7d9248b8c664..da8fd5ff9d0f 100644 --- a/drivers/gpu/drm/nouveau/nv04_fbcon.c +++ b/drivers/gpu/drm/nouveau/nv04_fbcon.c @@ -107,11 +107,11 @@ nv04_fbcon_imageblit(struct fb_info *info, const struct fb_image *image) ((image->dx + image->width) & 0xffff)); OUT_RING(chan, bg); OUT_RING(chan, fg); - OUT_RING(chan, (image->height << 16) | image->width); + OUT_RING(chan, (image->height << 16) | ALIGN(image->width, 8)); 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; + dsize = ALIGN(ALIGN(image->width, 8) * image->height, 32) >> 5; while (dsize) { int iter_len = dsize > 128 ? 128 : dsize; diff --git a/drivers/gpu/drm/nouveau/nv50_fbcon.c b/drivers/gpu/drm/nouveau/nv50_fbcon.c index 1aeb698e9707..af3d3c49411a 100644 --- a/drivers/gpu/drm/nouveau/nv50_fbcon.c +++ b/drivers/gpu/drm/nouveau/nv50_fbcon.c @@ -125,7 +125,7 @@ nv50_fbcon_imageblit(struct fb_info *info, const struct fb_image *image) OUT_RING(chan, 0); OUT_RING(chan, image->dy); - dwords = ALIGN(image->width * image->height, 32) >> 5; + dwords = ALIGN(ALIGN(image->width, 8) * image->height, 32) >> 5; while (dwords) { int push = dwords > 2047 ? 2047 : dwords; diff --git a/drivers/gpu/drm/nouveau/nvc0_fbcon.c b/drivers/gpu/drm/nouveau/nvc0_fbcon.c index 839f4c8c1805..054b6a056d99 100644 --- a/drivers/gpu/drm/nouveau/nvc0_fbcon.c +++ b/drivers/gpu/drm/nouveau/nvc0_fbcon.c @@ -125,7 +125,7 @@ nvc0_fbcon_imageblit(struct fb_info *info, const struct fb_image *image) OUT_RING (chan, 0); OUT_RING (chan, image->dy); - dwords = ALIGN(image->width * image->height, 32) >> 5; + dwords = ALIGN(ALIGN(image->width, 8) * image->height, 32) >> 5; while (dwords) { int push = dwords > 2047 ? 2047 : dwords; -- 2.20.1