view src/os/unix/ngx_darwin_init.c @ 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
line wrap: on
line source


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


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


char    ngx_darwin_kern_ostype[16];
char    ngx_darwin_kern_osrelease[128];
int     ngx_darwin_hw_ncpu;
int     ngx_darwin_kern_ipc_somaxconn;
u_long  ngx_darwin_net_inet_tcp_sendspace;

ngx_uint_t  ngx_debug_malloc;


static ngx_os_io_t ngx_darwin_io = {
    ngx_unix_recv,
    ngx_readv_chain,
    ngx_udp_unix_recv,
    ngx_unix_send,
    ngx_udp_unix_send,
    ngx_udp_unix_sendmsg_chain,
#if (NGX_HAVE_SENDFILE)
    ngx_darwin_sendfile_chain,
    NGX_IO_SENDFILE
#else
    ngx_writev_chain,
    0
#endif
};


typedef struct {
    char        *name;
    void        *value;
    size_t       size;
    ngx_uint_t   exists;
} sysctl_t;


sysctl_t sysctls[] = {
    { "hw.ncpu",
      &ngx_darwin_hw_ncpu,
      sizeof(ngx_darwin_hw_ncpu), 0 },

    { "net.inet.tcp.sendspace",
      &ngx_darwin_net_inet_tcp_sendspace,
      sizeof(ngx_darwin_net_inet_tcp_sendspace), 0 },

    { "kern.ipc.somaxconn",
      &ngx_darwin_kern_ipc_somaxconn,
      sizeof(ngx_darwin_kern_ipc_somaxconn), 0 },

    { NULL, NULL, 0, 0 }
};


void
ngx_debug_init(void)
{
#if (NGX_DEBUG_MALLOC)

    /*
     * MacOSX 10.6, 10.7:  MallocScribble fills freed memory with 0x55
     *                     and fills allocated memory with 0xAA.
     * MacOSX 10.4, 10.5:  MallocScribble fills freed memory with 0x55,
     *                     MallocPreScribble fills allocated memory with 0xAA.
     * MacOSX 10.3:        MallocScribble fills freed memory with 0x55,
     *                     and no way to fill allocated memory.
     */

    setenv("MallocScribble", "1", 0);

    ngx_debug_malloc = 1;

#else

    if (getenv("MallocScribble")) {
        ngx_debug_malloc = 1;
    }

#endif
}


ngx_int_t
ngx_os_specific_init(ngx_log_t *log)
{
    size_t      size;
    ngx_err_t   err;
    ngx_uint_t  i;

    size = sizeof(ngx_darwin_kern_ostype);
    if (sysctlbyname("kern.ostype", ngx_darwin_kern_ostype, &size, NULL, 0)
        == -1)
    {
        err = ngx_errno;

        if (err != NGX_ENOENT) {

            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "sysctlbyname(kern.ostype) failed");

            if (err != NGX_ENOMEM) {
                return NGX_ERROR;
            }

            ngx_darwin_kern_ostype[size - 1] = '\0';
        }
    }

    size = sizeof(ngx_darwin_kern_osrelease);
    if (sysctlbyname("kern.osrelease", ngx_darwin_kern_osrelease, &size,
                     NULL, 0)
        == -1)
    {
        err = ngx_errno;

        if (err != NGX_ENOENT) {

            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "sysctlbyname(kern.osrelease) failed");

            if (err != NGX_ENOMEM) {
                return NGX_ERROR;
            }

            ngx_darwin_kern_osrelease[size - 1] = '\0';
        }
    }

    for (i = 0; sysctls[i].name; i++) {
        size = sysctls[i].size;

        if (sysctlbyname(sysctls[i].name, sysctls[i].value, &size, NULL, 0)
            == 0)
        {
            sysctls[i].exists = 1;
            continue;
        }

        err = ngx_errno;

        if (err == NGX_ENOENT) {
            continue;
        }

        ngx_log_error(NGX_LOG_ALERT, log, err,
                      "sysctlbyname(%s) failed", sysctls[i].name);
        return NGX_ERROR;
    }

    ngx_ncpu = ngx_darwin_hw_ncpu;

    if (ngx_darwin_kern_ipc_somaxconn > 32767) {
        ngx_log_error(NGX_LOG_ALERT, log, 0,
                      "sysctl kern.ipc.somaxconn must be less than 32768");
        return NGX_ERROR;
    }

    ngx_tcp_nodelay_and_tcp_nopush = 1;

    ngx_os_io = ngx_darwin_io;

    return NGX_OK;
}


void
ngx_os_specific_status(ngx_log_t *log)
{
    u_long      value;
    ngx_uint_t  i;

    if (ngx_darwin_kern_ostype[0]) {
        ngx_log_error(NGX_LOG_NOTICE, log, 0, "OS: %s %s",
                      ngx_darwin_kern_ostype, ngx_darwin_kern_osrelease);
    }

    for (i = 0; sysctls[i].name; i++) {
        if (sysctls[i].exists) {
            if (sysctls[i].size == sizeof(long)) {
                value = *(long *) sysctls[i].value;

            } else {
                value = *(int *) sysctls[i].value;
            }

            ngx_log_error(NGX_LOG_NOTICE, log, 0, "%s: %l",
                          sysctls[i].name, value);
        }
    }
}