| Message ID | 1320399509-28669-1-git-send-email-armbru@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 11/04/2011 04:38 AM, Markus Armbruster wrote: > vga_putcharxy()'s underline code sets font_data to 0xffff instead of > 0xff. vga_putcharxy() then reads dmask16[0xffff>> 4] and > dmask4[0xffff>> 6]. In practice, these out-of-bounds subscripts > "only" put a few crap bits into the display surface. > > For 32 bit pixels, there's no array access. font_data's extra bits go > straight into the display surface. > > Broken when commit 6d6f7c28 implemented underline. > > Spotted by Coverity. > > Signed-off-by: Markus Armbruster<armbru@redhat.com> Applied. Thanks. Regards, Anthony Liguori > --- > console.c | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/console.c b/console.c > index e43de92..f6fe441 100644 > --- a/console.c > +++ b/console.c > @@ -467,7 +467,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, > font_data = *font_ptr++; > if (t_attrib->uline > && ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { > - font_data = 0xFFFF; > + font_data = 0xFF; > } > ((uint32_t *)d)[0] = (dmask16[(font_data>> 4)]& xorcol) ^ bgcol; > ((uint32_t *)d)[1] = (dmask16[(font_data>> 0)& 0xf]& xorcol) ^ bgcol; > @@ -480,7 +480,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, > font_data = *font_ptr++; > if (t_attrib->uline > && ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { > - font_data = 0xFFFF; > + font_data = 0xFF; > } > ((uint32_t *)d)[0] = (dmask4[(font_data>> 6)]& xorcol) ^ bgcol; > ((uint32_t *)d)[1] = (dmask4[(font_data>> 4)& 3]& xorcol) ^ bgcol; > @@ -493,7 +493,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, > for(i = 0; i< FONT_HEIGHT; i++) { > font_data = *font_ptr++; > if (t_attrib->uline&& ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { > - font_data = 0xFFFF; > + font_data = 0xFF; > } > ((uint32_t *)d)[0] = (-((font_data>> 7))& xorcol) ^ bgcol; > ((uint32_t *)d)[1] = (-((font_data>> 6)& 1)& xorcol) ^ bgcol;
diff --git a/console.c b/console.c index e43de92..f6fe441 100644 --- a/console.c +++ b/console.c @@ -467,7 +467,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, font_data = *font_ptr++; if (t_attrib->uline && ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { - font_data = 0xFFFF; + font_data = 0xFF; } ((uint32_t *)d)[0] = (dmask16[(font_data >> 4)] & xorcol) ^ bgcol; ((uint32_t *)d)[1] = (dmask16[(font_data >> 0) & 0xf] & xorcol) ^ bgcol; @@ -480,7 +480,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, font_data = *font_ptr++; if (t_attrib->uline && ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { - font_data = 0xFFFF; + font_data = 0xFF; } ((uint32_t *)d)[0] = (dmask4[(font_data >> 6)] & xorcol) ^ bgcol; ((uint32_t *)d)[1] = (dmask4[(font_data >> 4) & 3] & xorcol) ^ bgcol; @@ -493,7 +493,7 @@ static void vga_putcharxy(DisplayState *ds, int x, int y, int ch, for(i = 0; i < FONT_HEIGHT; i++) { font_data = *font_ptr++; if (t_attrib->uline && ((i == FONT_HEIGHT - 2) || (i == FONT_HEIGHT - 3))) { - font_data = 0xFFFF; + font_data = 0xFF; } ((uint32_t *)d)[0] = (-((font_data >> 7)) & xorcol) ^ bgcol; ((uint32_t *)d)[1] = (-((font_data >> 6) & 1) & xorcol) ^ bgcol;
vga_putcharxy()'s underline code sets font_data to 0xffff instead of 0xff. vga_putcharxy() then reads dmask16[0xffff >> 4] and dmask4[0xffff >> 6]. In practice, these out-of-bounds subscripts "only" put a few crap bits into the display surface. For 32 bit pixels, there's no array access. font_data's extra bits go straight into the display surface. Broken when commit 6d6f7c28 implemented underline. Spotted by Coverity. Signed-off-by: Markus Armbruster <armbru@redhat.com> --- console.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)