view src/os/unix/ngx_os.h @ 9112:d59277dd3d8c

QUIC: fixed post-close use-after-free. Previously, ngx_quic_close_connection() could be called in a way that QUIC connection was accessed after the call. In most cases the connection is not closed right away, but close timeout is scheduled. However, it's not always the case. Also, if the close process started earlier for a different reason, calling ngx_quic_close_connection() may actually close the connection. The connection object should not be accessed after that. Now, when possible, return statement is added to eliminate post-close connection object access. In other places ngx_quic_close_connection() is substituted with posting close event. Also, the new way of closing connection in ngx_quic_stream_cleanup_handler() fixes another problem in this function. Previously it passed stream connection instead of QUIC connection to ngx_quic_close_connection(). This could result in incomplete connection shutdown. One consequence of that could be that QUIC streams were freed without shutting down their application contexts. This could result in another use-after-free. Found by Coverity (CID 1530402).
author Roman Arutyunyan <arut@nginx.com>
date Mon, 22 May 2023 15:59:42 +0400
parents 56fc55e32f23
children 3d455e37abf8
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_OS_H_INCLUDED_
#define _NGX_OS_H_INCLUDED_


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


#define NGX_IO_SENDFILE    1


typedef ssize_t (*ngx_recv_pt)(ngx_connection_t *c, u_char *buf, size_t size);
typedef ssize_t (*ngx_recv_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);
typedef ssize_t (*ngx_send_pt)(ngx_connection_t *c, u_char *buf, size_t size);
typedef ngx_chain_t *(*ngx_send_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);

typedef struct {
    ngx_recv_pt        recv;
    ngx_recv_chain_pt  recv_chain;
    ngx_recv_pt        udp_recv;
    ngx_send_pt        send;
    ngx_send_pt        udp_send;
    ngx_send_chain_pt  udp_send_chain;
    ngx_send_chain_pt  send_chain;
    ngx_uint_t         flags;
} ngx_os_io_t;


ngx_int_t ngx_os_init(ngx_log_t *log);
void ngx_os_status(ngx_log_t *log);
ngx_int_t ngx_os_specific_init(ngx_log_t *log);
void ngx_os_specific_status(ngx_log_t *log);
ngx_int_t ngx_daemon(ngx_log_t *log);
ngx_int_t ngx_os_signal_process(ngx_cycle_t *cycle, char *sig, ngx_pid_t pid);


ssize_t ngx_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
ssize_t ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *entry, off_t limit);
ssize_t ngx_udp_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
ssize_t ngx_unix_send(ngx_connection_t *c, u_char *buf, size_t size);
ngx_chain_t *ngx_writev_chain(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);
ssize_t ngx_udp_unix_send(ngx_connection_t *c, u_char *buf, size_t size);
ngx_chain_t *ngx_udp_unix_sendmsg_chain(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);


#if (IOV_MAX > 64)
#define NGX_IOVS_PREALLOCATE  64
#else
#define NGX_IOVS_PREALLOCATE  IOV_MAX
#endif


typedef struct {
    struct iovec  *iovs;
    ngx_uint_t     count;
    size_t         size;
    ngx_uint_t     nalloc;
} ngx_iovec_t;

ngx_chain_t *ngx_output_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *in,
    size_t limit, ngx_log_t *log);


ssize_t ngx_writev(ngx_connection_t *c, ngx_iovec_t *vec);


extern ngx_os_io_t  ngx_os_io;
extern ngx_int_t    ngx_ncpu;
extern ngx_int_t    ngx_max_sockets;
extern ngx_uint_t   ngx_inherited_nonblocking;
extern ngx_uint_t   ngx_tcp_nodelay_and_tcp_nopush;


#if (NGX_FREEBSD)
#include <ngx_freebsd.h>


#elif (NGX_LINUX)
#include <ngx_linux.h>


#elif (NGX_SOLARIS)
#include <ngx_solaris.h>


#elif (NGX_DARWIN)
#include <ngx_darwin.h>
#endif


#endif /* _NGX_OS_H_INCLUDED_ */