@@ -93,9 +93,12 @@ static int next_tag_read(AVFormatContext *avctx, uint64_t *fsize)
AVIOContext *pb = avctx->pb;
char buf[36];
int len;
- uint64_t start_pos = avio_size(pb) - 256;
+ int64_t start_pos = avio_size(pb);
- avio_seek(pb, start_pos, SEEK_SET);
+ if (start_pos < 256)
+ return AVERROR_INVALIDDATA;
+
+ avio_seek(pb, start_pos - 256, SEEK_SET);
if (avio_read(pb, buf, sizeof(next_magic)) != sizeof(next_magic))
return -1;
if (memcmp(buf, next_magic, sizeof(next_magic)))
@@ -245,7 +248,10 @@ static int xbin_read_header(AVFormatContext *s)
return AVERROR(EIO);
if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
- bin->fsize = avio_size(pb) - 9 - st->codecpar->extradata_size;
+ int64_t fsize = avio_size(pb);
+ if (fsize < 9 + st->codecpar->extradata_size)
+ return 0;
+ bin->fsize = fsize - 9 - st->codecpar->extradata_size;
ff_sauce_read(s, &bin->fsize, NULL, 0);
avio_seek(pb, 9 + st->codecpar->extradata_size, SEEK_SET);
}
@@ -285,7 +291,10 @@ static int adf_read_header(AVFormatContext *s)
if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
int got_width = 0;
- bin->fsize = avio_size(pb) - 1 - 192 - 4096;
+ int64_t fsize = avio_size(pb);
+ if (fsize < 1 + 192 + 4096)
+ return 0;
+ bin->fsize = fsize - 1 - 192 - 4096;
st->codecpar->width = 80<<3;
ff_sauce_read(s, &bin->fsize, &got_width, 0);
if (st->codecpar->width < 8)
@@ -318,6 +327,7 @@ static int idf_read_header(AVFormatContext *s)
AVIOContext *pb = s->pb;
AVStream *st;
int got_width = 0, ret;
+ int64_t fsize;
if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
return AVERROR(EIO);
@@ -332,14 +342,18 @@ static int idf_read_header(AVFormatContext *s)
st->codecpar->extradata[0] = 16;
st->codecpar->extradata[1] = BINTEXT_PALETTE|BINTEXT_FONT;
- avio_seek(pb, avio_size(pb) - 4096 - 48, SEEK_SET);
+ fsize = avio_size(pb);
+ if (fsize < 12 + 4096 + 48)
+ return AVERROR_INVALIDDATA;
+ bin->fsize = fsize - 12 - 4096 - 48;
+
+ avio_seek(pb, bin->fsize + 12, SEEK_SET);
if (avio_read(pb, st->codecpar->extradata + 2 + 48, 4096) < 0)
return AVERROR(EIO);
if (avio_read(pb, st->codecpar->extradata + 2, 48) < 0)
return AVERROR(EIO);
- bin->fsize = avio_size(pb) - 12 - 4096 - 48;
ff_sauce_read(s, &bin->fsize, &got_width, 0);
if (st->codecpar->width < 8)
return AVERROR_INVALIDDATA;
Fixes: CID1604503 Overflowed constant Fixes: CID1604566 Overflowed constant Sponsored-by: Sovereign Tech Fund Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavformat/bintext.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-)