From 7b8c5b263bc680eff5710bee5994de39d47fc15e Mon Sep 17 00:00:00 2001 From: Vladimir Pantelic Date: Wed, 9 Jan 2013 17:04:09 +0100 Subject: vc1dec: prevent a crash due missing pred_flag parameter Handle pred_flag parameter not given to get_mvdata_interlaced() Signed-off-by: Vladimir Pantelic Signed-off-by: Luca Barbato --- libavcodec/vc1dec.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'libavcodec/vc1dec.c') diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c index d5d6884a73..c29f91ce11 100644 --- a/libavcodec/vc1dec.c +++ b/libavcodec/vc1dec.c @@ -1133,8 +1133,12 @@ static av_always_inline void get_mvdata_interlaced(VC1Context *v, int *dmv_x, *dmv_x = get_bits(gb, v->k_x); *dmv_y = get_bits(gb, v->k_y); if (v->numref) { - *pred_flag = *dmv_y & 1; - *dmv_y = (*dmv_y + *pred_flag) >> 1; + if (pred_flag) { + *pred_flag = *dmv_y & 1; + *dmv_y = (*dmv_y + *pred_flag) >> 1; + } else { + *dmv_y = (*dmv_y + (*dmv_y & 1)) >> 1; + } } } else { @@ -1160,7 +1164,7 @@ static av_always_inline void get_mvdata_interlaced(VC1Context *v, int *dmv_x, *dmv_y = (sign ^ ((val >> 1) + offs_tab[index1 >> v->numref])) - sign; } else *dmv_y = 0; - if (v->numref) + if (v->numref && pred_flag) *pred_flag = index1 & 1; } } -- cgit v1.2.3