static int http_start_receive_data(HTTPContext *c)
{
    int fd;
    int ret;
    int64_t ret64;

    if (c->stream->feed_opened) {
        http_log("Stream feed '%s' was not opened\n",
                 c->stream->feed_filename);
        return AVERROR(EINVAL);
    }

    /* Don't permit writing to this one */
    if (c->stream->readonly) {
        http_log("Cannot write to read-only file '%s'\n",
                 c->stream->feed_filename);
        return AVERROR(EINVAL);
    }

    /* open feed */
    fd = open(c->stream->feed_filename, O_RDWR);
    if (fd < 0) {
        ret = AVERROR(errno);
        http_log("Could not open feed file '%s': %s\n",
                 c->stream->feed_filename, strerror(errno));
        return ret;
    }
    c->feed_fd = fd;

    if (c->stream->truncate) {
        /* truncate feed file */
        ffm_write_write_index(c->feed_fd, FFM_PACKET_SIZE);
        http_log("Truncating feed file '%s'\n", c->stream->feed_filename);
        if (ftruncate(c->feed_fd, FFM_PACKET_SIZE) < 0) {
            ret = AVERROR(errno);
            http_log("Error truncating feed file '%s': %s\n",
                     c->stream->feed_filename, strerror(errno));
            return ret;
        }
    } else {
        ret64 = ffm_read_write_index(fd);
        if (ret64 < 0) {
            http_log("Error reading write index from feed file '%s': %s\n",
                     c->stream->feed_filename, strerror(errno));
            return ret64;
        }
        c->stream->feed_write_index = ret64;
    }

    c->stream->feed_write_index = FFMAX(ffm_read_write_index(fd),
                                        FFM_PACKET_SIZE);
    c->stream->feed_size = lseek(fd, 0, SEEK_END);
    lseek(fd, 0, SEEK_SET);

    /* init buffer input */
    c->buffer_ptr = c->buffer;
    c->buffer_end = c->buffer + FFM_PACKET_SIZE;
    c->stream->feed_opened = 1;
    c->chunked_encoding = !!av_stristr(c->buffer, "Transfer-Encoding: chunked");
    return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.