QUIC: ngx_quic_buffer_t use-after-free protection. Previously the last chain field of ngx_quic_buffer_t could still reference freed chains and buffers after calling ngx_quic_free_buffer(). While normally an ngx_quic_buffer_t object should not be used after freeing, resetting last_chain field would prevent a potential use-after-free.

/*
 * Copyright (C) Maxim Dounin
 * Copyright (C) Nginx, Inc.
 */


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


#if (NGX_HAVE_DLOPEN)

char *
ngx_dlerror(void)
{
    char  *err;

    err = (char *) dlerror();

    if (err == NULL) {
        return "";
    }

    return err;
}

#endif