Mp4: fixed possible pointer overflow on 32-bit platforms. On 32-bit platforms mp4->buffer_pos might overflow when a large enough (close to 4 gigabytes) atom is being skipped, resulting in incorrect memory addesses being read further in the code. In most cases this results in harmless errors being logged, though may also result in a segmentation fault if hitting unmapped pages. To address this, ngx_mp4_atom_next() now only increments mp4->buffer_pos up to mp4->buffer_end. This ensures that overflow cannot happen.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>


int ngx_file_type(char *file, ngx_file_info_t *sb)
{
    sb->dwFileAttributes = GetFileAttributes(file);

    if (sb->dwFileAttributes == INVALID_FILE_ATTRIBUTES) {
        return -1;
    }

    return 0;
}

/*
int ngx_stat(char *file, ngx_stat_t *sb)
{
    *sb = GetFileAttributes(file);

    if (*sb == INVALID_FILE_ATTRIBUTES) {
        return -1;
    }

    return 0;
}
*/