From 96c9bf7e2ae2ac331574cf5017a0381d184a45a8 Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Sat, 23 Mar 2019 01:29:55 +0000 Subject: [PATCH] video/console: Fix DM_VIDEO font glyph array indexing When the character to be printed on a DM_VIDEO console is from the "extended ASCII" range (0x80 - 0xff), it will be treated as a negative number, as it's declared as a signed char. This leads to negative array indicies into the glyph bitmap array, and random garbled characters. Cast the character to an unsigned type to make the index always positive and avoid an out-of-bounds access. Signed-off-by: Andre Przywara Reviewed-by: Simon Glass --- drivers/video/console_normal.c | 3 ++- drivers/video/console_rotate.c | 7 ++++--- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/video/console_normal.c b/drivers/video/console_normal.c index 2cfa510..7f01ee9 100644 --- a/drivers/video/console_normal.c +++ b/drivers/video/console_normal.c @@ -84,7 +84,8 @@ static int console_normal_putc_xy(struct udevice *dev, uint x_frac, uint y, return -EAGAIN; for (row = 0; row < VIDEO_FONT_HEIGHT; row++) { - uchar bits = video_fontdata[ch * VIDEO_FONT_HEIGHT + row]; + unsigned int idx = (u8)ch * VIDEO_FONT_HEIGHT + row; + uchar bits = video_fontdata[idx]; switch (vid_priv->bpix) { #ifdef CONFIG_VIDEO_BPP8 diff --git a/drivers/video/console_rotate.c b/drivers/video/console_rotate.c index f076570..71a5c5e 100644 --- a/drivers/video/console_rotate.c +++ b/drivers/video/console_rotate.c @@ -90,7 +90,7 @@ static int console_putc_xy_1(struct udevice *dev, uint x_frac, uint y, char ch) int i, col; int mask = 0x80; void *line; - uchar *pfont = video_fontdata + ch * VIDEO_FONT_HEIGHT; + uchar *pfont = video_fontdata + (u8)ch * VIDEO_FONT_HEIGHT; line = vid_priv->fb + (VID_TO_PIXEL(x_frac) + 1) * vid_priv->line_length - (y + 1) * pbytes; @@ -222,7 +222,8 @@ static int console_putc_xy_2(struct udevice *dev, uint x_frac, uint y, char ch) VIDEO_FONT_WIDTH - 1) * VNBYTES(vid_priv->bpix); for (row = 0; row < VIDEO_FONT_HEIGHT; row++) { - uchar bits = video_fontdata[ch * VIDEO_FONT_HEIGHT + row]; + unsigned int idx = (u8)ch * VIDEO_FONT_HEIGHT + row; + uchar bits = video_fontdata[idx]; switch (vid_priv->bpix) { #ifdef CONFIG_VIDEO_BPP8 @@ -348,7 +349,7 @@ static int console_putc_xy_3(struct udevice *dev, uint x_frac, uint y, char ch) void *line = vid_priv->fb + (vid_priv->ysize - VID_TO_PIXEL(x_frac) - 1) * vid_priv->line_length + y * pbytes; - uchar *pfont = video_fontdata + ch * VIDEO_FONT_HEIGHT; + uchar *pfont = video_fontdata + (u8)ch * VIDEO_FONT_HEIGHT; if (x_frac + VID_TO_POS(vc_priv->x_charsize) > vc_priv->xsize_frac) return -EAGAIN; -- 2.7.4