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| author | Martin Storsjö <martin@martin.st> | 2016-07-28 13:45:24 +0300 |
|---|---|---|
| committer | Martin Storsjö <martin@martin.st> | 2016-07-31 22:50:47 +0300 |
| commit | 7ebdffc353f3f0827864e8e3461fdc00cc243b14 (patch) | |
| tree | 85cbc666e10eb196f43efbc9bdb85e586485d895 /libavcodec | |
| parent | e328178da90f44690e0076f4dbfd16da9175f441 (diff) | |
| download | ffmpeg-7ebdffc353f3f0827864e8e3461fdc00cc243b14.tar.gz | |
dxv: Check to make sure we don't overrun buffers on corrupt inputs
Signed-off-by: Martin Storsjö <martin@martin.st>
Diffstat (limited to 'libavcodec')
| -rw-r--r-- | libavcodec/dxv.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/libavcodec/dxv.c b/libavcodec/dxv.c index 32137f5392..99327dface 100644 --- a/libavcodec/dxv.c +++ b/libavcodec/dxv.c @@ -125,7 +125,7 @@ static int dxv_decompress_dxt1(AVCodecContext *avctx) AV_WL32(ctx->tex_data + 4, bytestream2_get_le32(gbc)); /* Process input until the whole texture has been filled */ - while (pos < ctx->tex_size / 4) { + while (pos + 2 <= ctx->tex_size / 4) { CHECKPOINT(2); /* Copy two elements from a previous offset or from the input buffer */ @@ -178,7 +178,7 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx) AV_WL32(ctx->tex_data + 12, bytestream2_get_le32(gbc)); /* Process input until the whole texture has been filled */ - while (pos < ctx->tex_size / 4) { + while (pos + 2 <= ctx->tex_size / 4) { if (run) { run--; @@ -207,7 +207,7 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx) check += probe; } while (probe == 0xFFFF); } - while (check && pos < ctx->tex_size / 4) { + while (check && pos + 4 <= ctx->tex_size / 4) { prev = AV_RL32(ctx->tex_data + 4 * (pos - 4)); AV_WL32(ctx->tex_data + 4 * pos, prev); pos++; @@ -252,6 +252,8 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx) case 2: /* Copy two dwords from a previous index */ idx = 8 + bytestream2_get_le16(gbc); + if (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4) + return AVERROR_INVALIDDATA; prev = AV_RL32(ctx->tex_data + 4 * (pos - idx)); AV_WL32(ctx->tex_data + 4 * pos, prev); pos++; @@ -274,9 +276,13 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx) } CHECKPOINT(4); + if (pos + 2 > ctx->tex_size / 4) + return AVERROR_INVALIDDATA; /* Copy two elements from a previous offset or from the input buffer */ if (op) { + if (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4) + return AVERROR_INVALIDDATA; prev = AV_RL32(ctx->tex_data + 4 * (pos - idx)); AV_WL32(ctx->tex_data + 4 * pos, prev); pos++; @@ -287,6 +293,8 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx) } else { CHECKPOINT(4); + if (op && (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4)) + return AVERROR_INVALIDDATA; if (op) prev = AV_RL32(ctx->tex_data + 4 * (pos - idx)); else |