Mp4: added and updated sanity checks for "end" handling. When handling incorrect data in ngx_http_mp4_crop_stsc_data(), trak->end_chunk_samples might end up being arbitrary large, leading to reading before the buffer in ngx_http_mp4_update_stsz_atom(). Fix is to check that trak->end_chunk_samples corresponds to a memory within the stsz atom data. For consistency, trak->start_chunk_samples is checked similarly. Similarly, trak->end_chunk might end up being smaller than trak->start_chunk, leading to reading memory after the buffer in ngx_http_mp4_update_stco_atom() and ngx_http_mp4_update_co64_atom(). Corresponding checks are updated to explicitly test (trak->end_chunk - trak->start_chunk) instead of just checking trak->end_chunk and assuming it is larger than trak->start_chunk. This is generally in line with existing checks of (trak->end_sample - trak->start_sample) in ngx_http_mp4_update_stsz_atom(), where trak->end_sample might also become smaller than trak->start_sample when handling incorrect data in ngx_http_mp4_crop_stts_data().

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


if [ $USE_PCRE = YES -o $PCRE != NONE ]; then
    . auto/lib/pcre/conf

else
    if [ $USE_PCRE = DISABLED -a $HTTP = YES -a $HTTP_REWRITE = YES ]; then

cat << END

$0: error: the HTTP rewrite module requires the PCRE library.
You can either disable the module by using --without-http_rewrite_module
option or you have to enable the PCRE support.

END
        exit 1
    fi
fi


if [ $USE_OPENSSL = YES ]; then
    . auto/lib/openssl/conf
fi

if [ $USE_ZLIB = YES ]; then
    . auto/lib/zlib/conf
fi

if [ $USE_LIBXSLT != NO ]; then
    . auto/lib/libxslt/conf
fi

if [ $USE_LIBGD != NO ]; then
    . auto/lib/libgd/conf
fi

if [ $USE_PERL != NO ]; then
    . auto/lib/perl/conf
fi

if [ $USE_GEOIP != NO ]; then
    . auto/lib/geoip/conf
fi

if [ $NGX_GOOGLE_PERFTOOLS = YES ]; then
    . auto/lib/google-perftools/conf
fi

if [ $NGX_LIBATOMIC != NO ]; then
    . auto/lib/libatomic/conf
fi