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vc1: avoid reading beyond the last line in vc1_draw_sprites()

Fixes overread

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>
This commit is contained in:
Michael Niedermayer 2012-07-28 16:27:55 +06:00 committed by Kostya Shishkov
parent 1100acbab2
commit 2bf369b60c

View File

@ -4938,15 +4938,17 @@ static void vc1_draw_sprites(VC1Context *v, SpriteData* sd)
int iline = s->current_picture.f.linesize[plane]; int iline = s->current_picture.f.linesize[plane];
int ycoord = yoff[sprite] + yadv[sprite] * row; int ycoord = yoff[sprite] + yadv[sprite] * row;
int yline = ycoord >> 16; int yline = ycoord >> 16;
int next_line;
ysub[sprite] = ycoord & 0xFFFF; ysub[sprite] = ycoord & 0xFFFF;
if (sprite) { if (sprite) {
iplane = s->last_picture.f.data[plane]; iplane = s->last_picture.f.data[plane];
iline = s->last_picture.f.linesize[plane]; iline = s->last_picture.f.linesize[plane];
} }
next_line = FFMIN(yline + 1, (v->sprite_height >> !!plane) - 1) * iline;
if (!(xoff[sprite] & 0xFFFF) && xadv[sprite] == 1 << 16) { if (!(xoff[sprite] & 0xFFFF) && xadv[sprite] == 1 << 16) {
src_h[sprite][0] = iplane + (xoff[sprite] >> 16) + yline * iline; src_h[sprite][0] = iplane + (xoff[sprite] >> 16) + yline * iline;
if (ysub[sprite]) if (ysub[sprite])
src_h[sprite][1] = iplane + (xoff[sprite] >> 16) + (yline + 1) * iline; src_h[sprite][1] = iplane + (xoff[sprite] >> 16) + next_line;
} else { } else {
if (sr_cache[sprite][0] != yline) { if (sr_cache[sprite][0] != yline) {
if (sr_cache[sprite][1] == yline) { if (sr_cache[sprite][1] == yline) {
@ -4958,7 +4960,9 @@ static void vc1_draw_sprites(VC1Context *v, SpriteData* sd)
} }
} }
if (ysub[sprite] && sr_cache[sprite][1] != yline + 1) { if (ysub[sprite] && sr_cache[sprite][1] != yline + 1) {
v->vc1dsp.sprite_h(v->sr_rows[sprite][1], iplane + (yline + 1) * iline, xoff[sprite], xadv[sprite], width); v->vc1dsp.sprite_h(v->sr_rows[sprite][1],
iplane + next_line, xoff[sprite],
xadv[sprite], width);
sr_cache[sprite][1] = yline + 1; sr_cache[sprite][1] = yline + 1;
} }
src_h[sprite][0] = v->sr_rows[sprite][0]; src_h[sprite][0] = v->sr_rows[sprite][0];