From: Mikulas Patocka Date: Thu, 28 Jul 2016 22:56:13 +0000 (-0400) Subject: drm/nouveau/fbcon: fix font width not divisible by 8 X-Git-Tag: v3.18.40~16 X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b8463d761945b76bcd49cf9c9f3f4671ea59aa3f;p=linux drm/nouveau/fbcon: fix font width not divisible by 8 [ Upstream commit 28668f43b8e421634e1623f72a879812288dd06b ] 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 Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/nouveau/nv04_fbcon.c b/drivers/gpu/drm/nouveau/nv04_fbcon.c index 7ab83f7f2763..ec974273d1e4 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 cb2a71ada99e..8462f72e8819 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 69f760e8c54f..90552420c217 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;