ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinha...@outlook.com> | Wed Apr 16 11:03:53 2025 +0200| [3cf21217b5063d9758582d1cab325e3c91c848f2] | committer: Andreas Rheinhardt
avcodec/dvbsubenc: Check nb_colors before using it Avoids a potential overflow when multiplying nb_colors by 6. Also make the nb_colors check a bit more strict. Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@outlook.com> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3cf21217b5063d9758582d1cab325e3c91c848f2 --- libavcodec/dvbsubenc.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/libavcodec/dvbsubenc.c b/libavcodec/dvbsubenc.c index 4844c3deb5..113bb320a9 100644 --- a/libavcodec/dvbsubenc.c +++ b/libavcodec/dvbsubenc.c @@ -329,24 +329,23 @@ static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size, if (h->num_rects) { for (clut_id = 0; clut_id < h->num_rects; clut_id++) { - if (buf_size < 6 + h->rects[clut_id]->nb_colors * 6) - return AVERROR_BUFFER_TOO_SMALL; - /* CLUT segment */ - if (h->rects[clut_id]->nb_colors <= 4) { + if (h->rects[clut_id]->nb_colors <= 4U) { /* 2 bpp, some decoders do not support it correctly */ bpp_index = 0; - } else if (h->rects[clut_id]->nb_colors <= 16) { + } else if (h->rects[clut_id]->nb_colors <= 16U) { /* 4 bpp, standard encoding */ bpp_index = 1; - } else if (h->rects[clut_id]->nb_colors <= 256) { + } else if (h->rects[clut_id]->nb_colors <= 256U) { /* 8 bpp, standard encoding */ bpp_index = 2; } else { return AVERROR(EINVAL); } + if (buf_size < 6 + h->rects[clut_id]->nb_colors * 6) + return AVERROR_BUFFER_TOO_SMALL; /* CLUT segment */ *q++ = 0x0f; /* sync byte */ _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
