From 8370e426e42f2e4b9d14a1fb8107ecfe5163ce7f Mon Sep 17 00:00:00 2001 From: "Ronald S. Bultje" Date: Fri, 28 Oct 2011 23:50:04 -0700 Subject: [PATCH] vp3: fix oob read for negative tokens and memleaks on error. --- libavcodec/vp3.c | 59 ++++++++++++++++++++++++++++++++++++------------ 1 file changed, 45 insertions(+), 14 deletions(-) diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c index 36715bb0c7..ce14e63735 100644 --- a/libavcodec/vp3.c +++ b/libavcodec/vp3.c @@ -45,6 +45,7 @@ #define FRAGMENT_PIXELS 8 static av_cold int vp3_decode_end(AVCodecContext *avctx); +static void vp3_decode_flush(AVCodecContext *avctx); //FIXME split things out into their own arrays typedef struct Vp3Fragment { @@ -890,7 +891,7 @@ static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb, /* decode a VLC into a token */ token = get_vlc2(gb, vlc_table, 11, 3); /* use the token to get a zero run, a coefficient, and an eob run */ - if (token <= 6) { + if ((unsigned) token <= 6U) { eob_run = eob_run_base[token]; if (eob_run_get_bits[token]) eob_run += get_bits(gb, eob_run_get_bits[token]); @@ -908,7 +909,7 @@ static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb, coeff_i += eob_run; eob_run = 0; } - } else { + } else if (token >= 0) { bits_to_get = coeff_get_bits[token]; if (bits_to_get) bits_to_get = get_bits(gb, bits_to_get); @@ -942,6 +943,10 @@ static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb, for (i = coeff_index+1; i <= coeff_index+zero_run; i++) s->num_coded_frags[plane][i]--; coeff_i++; + } else { + av_log(s->avctx, AV_LOG_ERROR, + "Invalid token %d\n", token); + return -1; } } @@ -991,6 +996,8 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb) /* unpack the Y plane DC coefficients */ residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_y_table], 0, 0, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; /* reverse prediction of the Y-plane DC coefficients */ reverse_dc_prediction(s, 0, s->fragment_width[0], s->fragment_height[0]); @@ -998,8 +1005,12 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb) /* unpack the C plane DC coefficients */ residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_c_table], 0, 1, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_c_table], 0, 2, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; /* reverse prediction of the C-plane DC coefficients */ if (!(s->avctx->flags & CODEC_FLAG_GRAY)) @@ -1036,11 +1047,17 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb) for (i = 1; i <= 63; i++) { residual_eob_run = unpack_vlcs(s, gb, y_tables[i], i, 0, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i, 1, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i, 2, residual_eob_run); + if (residual_eob_run < 0) + return residual_eob_run; } return 0; @@ -1777,10 +1794,15 @@ static int vp3_update_thread_context(AVCodecContext *dst, const AVCodecContext * Vp3DecodeContext *s = dst->priv_data, *s1 = src->priv_data; int qps_changed = 0, i, err; +#define copy_fields(to, from, start_field, end_field) memcpy(&to->start_field, &from->start_field, (char*)&to->end_field - (char*)&to->start_field) + if (!s1->current_frame.data[0] ||s->width != s1->width - ||s->height!= s1->height) + ||s->height!= s1->height) { + if (s != s1) + copy_fields(s, s1, golden_frame, current_frame); return -1; + } if (s != s1) { // init tables if the first frame hasn't been decoded @@ -1796,8 +1818,6 @@ static int vp3_update_thread_context(AVCodecContext *dst, const AVCodecContext * memcpy(s->motion_val[1], s1->motion_val[1], c_fragment_count * sizeof(*s->motion_val[1])); } -#define copy_fields(to, from, start_field, end_field) memcpy(&to->start_field, &from->start_field, (char*)&to->end_field - (char*)&to->start_field) - // copy previous frame data copy_fields(s, s1, golden_frame, dsp); @@ -1987,9 +2007,6 @@ static av_cold int vp3_decode_end(AVCodecContext *avctx) Vp3DecodeContext *s = avctx->priv_data; int i; - if (avctx->is_copy && !s->current_frame.data[0]) - return 0; - av_free(s->superblock_coding); av_free(s->all_fragments); av_free(s->coded_fragment_list[0]); @@ -2016,12 +2033,7 @@ static av_cold int vp3_decode_end(AVCodecContext *avctx) free_vlc(&s->motion_vector_vlc); /* release all frames */ - if (s->golden_frame.data[0]) - ff_thread_release_buffer(avctx, &s->golden_frame); - if (s->last_frame.data[0] && s->last_frame.type != FF_BUFFER_TYPE_COPY) - ff_thread_release_buffer(avctx, &s->last_frame); - /* no need to release the current_frame since it will always be pointing - * to the same frame as either the golden or last frame */ + vp3_decode_flush(avctx); return 0; } @@ -2341,6 +2353,23 @@ static void vp3_decode_flush(AVCodecContext *avctx) ff_thread_release_buffer(avctx, &s->current_frame); } +static int vp3_init_thread_copy(AVCodecContext *avctx) +{ + Vp3DecodeContext *s = avctx->priv_data; + + s->superblock_coding = NULL; + s->all_fragments = NULL; + s->coded_fragment_list[0] = NULL; + s->dct_tokens_base = NULL; + s->superblock_fragments = NULL; + s->macroblock_coding = NULL; + s->motion_val[0] = NULL; + s->motion_val[1] = NULL; + s->edge_emu_buffer = NULL; + + return 0; +} + AVCodec ff_theora_decoder = { .name = "theora", .type = AVMEDIA_TYPE_VIDEO, @@ -2352,6 +2381,7 @@ AVCodec ff_theora_decoder = { .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_FRAME_THREADS, .flush = vp3_decode_flush, .long_name = NULL_IF_CONFIG_SMALL("Theora"), + .init_thread_copy = ONLY_IF_THREADS_ENABLED(vp3_init_thread_copy), .update_thread_context = ONLY_IF_THREADS_ENABLED(vp3_update_thread_context) }; #endif @@ -2367,5 +2397,6 @@ AVCodec ff_vp3_decoder = { .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_FRAME_THREADS, .flush = vp3_decode_flush, .long_name = NULL_IF_CONFIG_SMALL("On2 VP3"), + .init_thread_copy = ONLY_IF_THREADS_ENABLED(vp3_init_thread_copy), .update_thread_context = ONLY_IF_THREADS_ENABLED(vp3_update_thread_context) };