diff options
Diffstat (limited to 'libavcodec/4xm.c')
-rw-r--r-- | libavcodec/4xm.c | 104 |
1 files changed, 79 insertions, 25 deletions
diff --git a/libavcodec/4xm.c b/libavcodec/4xm.c index 21bde52..e6638c7 100644 --- a/libavcodec/4xm.c +++ b/libavcodec/4xm.c @@ -2,20 +2,20 @@ * 4XM codec * Copyright (c) 2003 Michael Niedermayer * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * Libav is distributed in the hope that it will be useful, + * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -133,7 +133,9 @@ typedef struct FourXContext{ GetBitContext pre_gb; ///< ac/dc prefix GetBitContext gb; const uint8_t *bytestream; + const uint8_t *bytestream_end; const uint16_t *wordstream; + const uint16_t *wordstream_end; int mv[256]; VLC pre_vlc; int last_dc; @@ -328,6 +330,10 @@ static void decode_p_block(FourXContext *f, uint16_t *dst, uint16_t *src, int lo assert(code>=0 && code<=6); if(code == 0){ + if (f->bytestream_end - f->bytestream < 1){ + av_log(f->avctx, AV_LOG_ERROR, "bytestream overread\n"); + return; + } src += f->mv[ *f->bytestream++ ]; if(start > src || src > end){ av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n"); @@ -345,15 +351,31 @@ static void decode_p_block(FourXContext *f, uint16_t *dst, uint16_t *src, int lo }else if(code == 3 && f->version<2){ mcdc(dst, src, log2w, h, stride, 1, 0); }else if(code == 4){ + if (f->bytestream_end - f->bytestream < 1){ + av_log(f->avctx, AV_LOG_ERROR, "bytestream overread\n"); + return; + } src += f->mv[ *f->bytestream++ ]; if(start > src || src > end){ av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n"); return; } + if (f->wordstream_end - f->wordstream < 1){ + av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n"); + return; + } mcdc(dst, src, log2w, h, stride, 1, av_le2ne16(*f->wordstream++)); }else if(code == 5){ + if (f->wordstream_end - f->wordstream < 1){ + av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n"); + return; + } mcdc(dst, src, log2w, h, stride, 0, av_le2ne16(*f->wordstream++)); }else if(code == 6){ + if (f->wordstream_end - f->wordstream < 2){ + av_log(f->avctx, AV_LOG_ERROR, "wordstream overread\n"); + return; + } if(log2w){ dst[0] = av_le2ne16(*f->wordstream++); dst[1] = av_le2ne16(*f->wordstream++); @@ -375,6 +397,8 @@ static int decode_p_frame(FourXContext *f, const uint8_t *buf, int length){ if(f->version>1){ extra=20; + if (length < extra) + return -1; bitstream_size= AV_RL32(buf+8); wordstream_size= AV_RL32(buf+12); bytestream_size= AV_RL32(buf+16); @@ -385,11 +409,10 @@ static int decode_p_frame(FourXContext *f, const uint8_t *buf, int length){ bytestream_size= FFMAX(length - bitstream_size - wordstream_size, 0); } - if(bitstream_size+ bytestream_size+ wordstream_size + extra != length - || bitstream_size > (1<<26) - || bytestream_size > (1<<26) - || wordstream_size > (1<<26) - ){ + if (bitstream_size > length || + bytestream_size > length - bitstream_size || + wordstream_size > length - bytestream_size - bitstream_size || + extra > length - bytestream_size - bitstream_size - wordstream_size){ av_log(f->avctx, AV_LOG_ERROR, "lengths %d %d %d %d\n", bitstream_size, bytestream_size, wordstream_size, bitstream_size+ bytestream_size+ wordstream_size - length); return -1; @@ -403,7 +426,9 @@ static int decode_p_frame(FourXContext *f, const uint8_t *buf, int length){ init_get_bits(&f->gb, f->bitstream_buffer, 8*bitstream_size); f->wordstream= (const uint16_t*)(buf + extra + bitstream_size); + f->wordstream_end= f->wordstream + wordstream_size/2; f->bytestream= buf + extra + bitstream_size + wordstream_size; + f->bytestream_end = f->bytestream + bytestream_size; init_mv(f); @@ -532,7 +557,7 @@ static int decode_i_mb(FourXContext *f){ return 0; } -static const uint8_t *read_huffman_tables(FourXContext *f, const uint8_t * const buf){ +static const uint8_t *read_huffman_tables(FourXContext *f, const uint8_t * const buf, int buf_size){ int frequency[512]; uint8_t flag[512]; int up[512]; @@ -540,6 +565,7 @@ static const uint8_t *read_huffman_tables(FourXContext *f, const uint8_t * const int bits_tab[257]; int start, end; const uint8_t *ptr= buf; + const uint8_t *ptr_end = buf + buf_size; int j; memset(frequency, 0, sizeof(frequency)); @@ -550,6 +576,8 @@ static const uint8_t *read_huffman_tables(FourXContext *f, const uint8_t * const for(;;){ int i; + if (start <= end && ptr_end - ptr < end - start + 1 + 1) + return NULL; for(i=start; i<=end; i++){ frequency[i]= *ptr++; } @@ -623,10 +651,13 @@ static int decode_i2_frame(FourXContext *f, const uint8_t *buf, int length){ const int height= f->avctx->height; uint16_t *dst= (uint16_t*)f->current_picture.data[0]; const int stride= f->current_picture.linesize[0]>>1; + const uint8_t *buf_end = buf + length; for(y=0; y<height; y+=16){ for(x=0; x<width; x+=16){ unsigned int color[4], bits; + if (buf_end - buf < 8) + return -1; memset(color, 0, sizeof(color)); //warning following is purely guessed ... color[0]= bytestream_get_le16(&buf); @@ -660,18 +691,23 @@ static int decode_i_frame(FourXContext *f, const uint8_t *buf, int length){ uint16_t *dst= (uint16_t*)f->current_picture.data[0]; const int stride= f->current_picture.linesize[0]>>1; const unsigned int bitstream_size= AV_RL32(buf); - const int token_count av_unused = AV_RL32(buf + bitstream_size + 8); - unsigned int prestream_size= 4*AV_RL32(buf + bitstream_size + 4); - const uint8_t *prestream= buf + bitstream_size + 12; + unsigned int prestream_size; + const uint8_t *prestream; + + if (bitstream_size > (1<<26) || length < bitstream_size + 12) + return -1; + prestream_size = 4*AV_RL32(buf + bitstream_size + 4); + prestream = buf + bitstream_size + 12; - if(prestream_size + bitstream_size + 12 != length - || bitstream_size > (1<<26) - || prestream_size > (1<<26)){ + if (prestream_size > (1<<26) || + prestream_size != length - (bitstream_size + 12)){ av_log(f->avctx, AV_LOG_ERROR, "size mismatch %d %d %d\n", prestream_size, bitstream_size, length); return -1; } - prestream= read_huffman_tables(f, prestream); + prestream= read_huffman_tables(f, prestream, buf + length - prestream); + if (!prestream) + return -1; init_get_bits(&f->gb, buf + 4, 8*bitstream_size); @@ -713,6 +749,8 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *p, temp; int i, frame_4cc, frame_size; + if (buf_size < 12) + return AVERROR_INVALIDDATA; frame_4cc= AV_RL32(buf); if(buf_size != AV_RL32(buf+4)+8 || buf_size < 20){ av_log(f->avctx, AV_LOG_ERROR, "size mismatch %d %d\n", buf_size, AV_RL32(buf+4)); @@ -725,6 +763,11 @@ static int decode_frame(AVCodecContext *avctx, const int whole_size= AV_RL32(buf+16); CFrameBuffer *cfrm; + if (data_size < 0 || whole_size < 0){ + av_log(f->avctx, AV_LOG_ERROR, "sizes invalid\n"); + return AVERROR_INVALIDDATA; + } + for(i=0; i<CFRAME_BUFFER_COUNT; i++){ if(f->cfrm[i].id && f->cfrm[i].id < avctx->frame_number) av_log(f->avctx, AV_LOG_ERROR, "lost c frame %d\n", f->cfrm[i].id); @@ -741,6 +784,8 @@ static int decode_frame(AVCodecContext *avctx, } cfrm= &f->cfrm[i]; + if (data_size > UINT_MAX - cfrm->size - FF_INPUT_BUFFER_PADDING_SIZE) + return AVERROR_INVALIDDATA; cfrm->data= av_fast_realloc(cfrm->data, &cfrm->allocated_size, cfrm->size + data_size + FF_INPUT_BUFFER_PADDING_SIZE); if(!cfrm->data){ //explicit check needed as memcpy below might not catch a NULL av_log(f->avctx, AV_LOG_ERROR, "realloc falure"); @@ -776,23 +821,24 @@ static int decode_frame(AVCodecContext *avctx, avctx->flags |= CODEC_FLAG_EMU_EDGE; // alternatively we would have to use our own buffer management - if(p->data[0]) - avctx->release_buffer(avctx, p); - p->reference= 1; - if(avctx->get_buffer(avctx, p) < 0){ - av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + if (avctx->reget_buffer(avctx, p) < 0) { + av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } if(frame_4cc == AV_RL32("ifr2")){ p->pict_type= AV_PICTURE_TYPE_I; - if(decode_i2_frame(f, buf-4, frame_size) < 0) + if(decode_i2_frame(f, buf-4, frame_size+4) < 0){ + av_log(f->avctx, AV_LOG_ERROR, "decode i2 frame failed\n"); return -1; + } }else if(frame_4cc == AV_RL32("ifrm")){ p->pict_type= AV_PICTURE_TYPE_I; - if(decode_i_frame(f, buf, frame_size) < 0) + if(decode_i_frame(f, buf, frame_size) < 0){ + av_log(f->avctx, AV_LOG_ERROR, "decode i frame failed\n"); return -1; + } }else if(frame_4cc == AV_RL32("pfrm") || frame_4cc == AV_RL32("pfr2")){ if(!f->last_picture.data[0]){ f->last_picture.reference= 1; @@ -803,8 +849,10 @@ static int decode_frame(AVCodecContext *avctx, } p->pict_type= AV_PICTURE_TYPE_P; - if(decode_p_frame(f, buf, frame_size) < 0) + if(decode_p_frame(f, buf, frame_size) < 0){ + av_log(f->avctx, AV_LOG_ERROR, "decode p frame failed\n"); return -1; + } }else if(frame_4cc == AV_RL32("snd_")){ av_log(avctx, AV_LOG_ERROR, "ignoring snd_ chunk length:%d\n", buf_size); }else{ @@ -837,7 +885,13 @@ static av_cold int decode_init(AVCodecContext *avctx){ av_log(avctx, AV_LOG_ERROR, "extradata wrong or missing\n"); return 1; } + if((avctx->width % 16) || (avctx->height % 16)) { + av_log(avctx, AV_LOG_ERROR, "unsupported width/height\n"); + return AVERROR_INVALIDDATA; + } + avcodec_get_frame_defaults(&f->current_picture); + avcodec_get_frame_defaults(&f->last_picture); f->version= AV_RL32(avctx->extradata)>>16; common_init(avctx); init_vlcs(f); |