Module: libav Branch: release/0.8 Commit: 88c3cc019c8f3ebb9a41ce49c4b7ee6242836849
Author: Ronald S. Bultje <[email protected]> Committer: Reinhard Tartler <[email protected]> Date: Thu Mar 8 17:09:27 2012 -0800 cook: expand dither_tab[], and make sure indexes into it don't overflow. Fixes overflows in accessing dither_tab[]. Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind CC: [email protected] (cherry picked from commit 442c3a8cb1785d74f8e2d7ab35b1862b7088436b) Signed-off-by: Reinhard Tartler <[email protected]> --- libavcodec/cook.c | 6 +++++- libavcodec/cookdata.h | 4 ++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/libavcodec/cook.c b/libavcodec/cook.c index dc4c2ab..7c499f0 100644 --- a/libavcodec/cook.c +++ b/libavcodec/cook.c @@ -507,7 +507,11 @@ static inline void expand_category(COOKContext *q, int *category, { int i; for (i = 0; i < q->num_vectors; i++) - ++category[category_index[i]]; + { + int idx = category_index[i]; + if (++category[idx] >= FF_ARRAY_ELEMS(dither_tab)) + --category[idx]; + } } /** diff --git a/libavcodec/cookdata.h b/libavcodec/cookdata.h index e8d6ebf..6825a44 100644 --- a/libavcodec/cookdata.h +++ b/libavcodec/cookdata.h @@ -36,8 +36,8 @@ static const int expbits_tab[8] = { 52,47,43,37,29,22,16,0, }; -static const float dither_tab[8] = { - 0.0, 0.0, 0.0, 0.0, 0.0, 0.176777, 0.25, 0.707107, +static const float dither_tab[9] = { + 0.0, 0.0, 0.0, 0.0, 0.0, 0.176777, 0.25, 0.707107, 1.0 }; static const float quant_centroid_tab[7][14] = { _______________________________________________ libav-commits mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-commits
