Resolver: fixed possible use-after-free while resolving PTR. Previously, if a response to the PTR request was cached, and ngx_resolver_dup() failed to allocate memory for the resulting name, then the original node was freed but left in expire_queue. A subsequent address resolving would end up in a use-after-free memory access of the node either in ngx_resolver_expire() or ngx_resolver_process_ptr(), when accessing it through expire_queue. The fix is to leave the resolver node intact.

/*
 * Copyright (C) Roman Arutyunyan
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_PROXY_PROTOCOL_H_INCLUDED_
#define _NGX_PROXY_PROTOCOL_H_INCLUDED_


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


#define NGX_PROXY_PROTOCOL_MAX_HEADER  107


u_char *ngx_proxy_protocol_read(ngx_connection_t *c, u_char *buf,
    u_char *last);
u_char *ngx_proxy_protocol_write(ngx_connection_t *c, u_char *buf,
    u_char *last);


#endif /* _NGX_PROXY_PROTOCOL_H_INCLUDED_ */