The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/kern/exec_aout.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*      $NetBSD: exec_aout.c,v 1.33 2005/12/11 12:24:29 christos Exp $  */
    2 
    3 /*
    4  * Copyright (c) 1993, 1994 Christopher G. Demetriou
    5  * All rights reserved.
    6  *
    7  * Redistribution and use in source and binary forms, with or without
    8  * modification, are permitted provided that the following conditions
    9  * are met:
   10  * 1. Redistributions of source code must retain the above copyright
   11  *    notice, this list of conditions and the following disclaimer.
   12  * 2. Redistributions in binary form must reproduce the above copyright
   13  *    notice, this list of conditions and the following disclaimer in the
   14  *    documentation and/or other materials provided with the distribution.
   15  * 3. All advertising materials mentioning features or use of this software
   16  *    must display the following acknowledgement:
   17  *      This product includes software developed by Christopher G. Demetriou.
   18  * 4. The name of the author may not be used to endorse or promote products
   19  *    derived from this software without specific prior written permission
   20  *
   21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   31  */
   32 
   33 #include <sys/cdefs.h>
   34 __KERNEL_RCSID(0, "$NetBSD: exec_aout.c,v 1.33 2005/12/11 12:24:29 christos Exp $");
   35 
   36 #include <sys/param.h>
   37 #include <sys/systm.h>
   38 #include <sys/proc.h>
   39 #include <sys/malloc.h>
   40 #include <sys/vnode.h>
   41 #include <sys/exec.h>
   42 #include <sys/exec_aout.h>
   43 #include <sys/resourcevar.h>
   44 
   45 #include <uvm/uvm_extern.h>
   46 
   47 /*
   48  * exec_aout_makecmds(): Check if it's an a.out-format executable.
   49  *
   50  * Given a lwp pointer and an exec package pointer, see if the referent
   51  * of the epp is in a.out format.  First check 'standard' magic numbers for
   52  * this architecture.  If that fails, try a CPU-dependent hook.
   53  *
   54  * This function, in the former case, or the hook, in the latter, is
   55  * responsible for creating a set of vmcmds which can be used to build
   56  * the process's vm space and inserting them into the exec package.
   57  */
   58 
   59 int
   60 exec_aout_makecmds(struct lwp *l, struct exec_package *epp)
   61 {
   62         u_long midmag, magic;
   63         u_short mid;
   64         int error;
   65         struct exec *execp = epp->ep_hdr;
   66 
   67         if (epp->ep_hdrvalid < sizeof(struct exec))
   68                 return ENOEXEC;
   69 
   70         midmag = ntohl(execp->a_midmag);
   71         mid = (midmag >> 16) & 0x3ff;
   72         magic = midmag & 0xffff;
   73 
   74         midmag = mid << 16 | magic;
   75 
   76         switch (midmag) {
   77         case (MID_MACHINE << 16) | ZMAGIC:
   78                 error = exec_aout_prep_zmagic(l, epp);
   79                 break;
   80         case (MID_MACHINE << 16) | NMAGIC:
   81                 error = exec_aout_prep_nmagic(l, epp);
   82                 break;
   83         case (MID_MACHINE << 16) | OMAGIC:
   84                 error = exec_aout_prep_omagic(l, epp);
   85                 break;
   86         default:
   87                 error = cpu_exec_aout_makecmds(l, epp);
   88         }
   89 
   90         if (error)
   91                 kill_vmcmds(&epp->ep_vmcmds);
   92 
   93         return error;
   94 }
   95 
   96 /*
   97  * exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package
   98  *
   99  * First, set of the various offsets/lengths in the exec package.
  100  *
  101  * Then, mark the text image busy (so it can be demand paged) or error
  102  * out if this is not possible.  Finally, set up vmcmds for the
  103  * text, data, bss, and stack segments.
  104  */
  105 
  106 int
  107 exec_aout_prep_zmagic(struct lwp *l, struct exec_package *epp)
  108 {
  109         struct exec *execp = epp->ep_hdr;
  110         int error;
  111 
  112         epp->ep_taddr = AOUT_LDPGSZ;
  113         epp->ep_tsize = execp->a_text;
  114         epp->ep_daddr = epp->ep_taddr + execp->a_text;
  115         epp->ep_dsize = execp->a_data + execp->a_bss;
  116         epp->ep_entry = execp->a_entry;
  117 
  118         error = vn_marktext(epp->ep_vp);
  119         if (error)
  120                 return (error);
  121 
  122         /* set up command for text segment */
  123         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_text),
  124             epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
  125 
  126         /* set up command for data segment */
  127         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_data),
  128             epp->ep_daddr, epp->ep_vp, execp->a_text,
  129             VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  130 
  131         /* set up command for bss segment */
  132         if (execp->a_bss > 0)
  133                 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
  134                     epp->ep_daddr + execp->a_data, NULLVP, 0,
  135                     VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  136 
  137         return (*epp->ep_esch->es_setup_stack)(l, epp);
  138 }
  139 
  140 /*
  141  * exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package
  142  */
  143 
  144 int
  145 exec_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
  146 {
  147         struct exec *execp = epp->ep_hdr;
  148         long bsize, baddr;
  149 
  150         epp->ep_taddr = AOUT_LDPGSZ;
  151         epp->ep_tsize = execp->a_text;
  152         epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, AOUT_LDPGSZ);
  153         epp->ep_dsize = execp->a_data + execp->a_bss;
  154         epp->ep_entry = execp->a_entry;
  155 
  156         /* set up command for text segment */
  157         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
  158             epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
  159             VM_PROT_READ|VM_PROT_EXECUTE);
  160 
  161         /* set up command for data segment */
  162         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
  163             epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
  164             VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  165 
  166         /* set up command for bss segment */
  167         baddr = round_page(epp->ep_daddr + execp->a_data);
  168         bsize = epp->ep_daddr + epp->ep_dsize - baddr;
  169         if (bsize > 0)
  170                 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
  171                     NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  172 
  173         return (*epp->ep_esch->es_setup_stack)(l, epp);
  174 }
  175 
  176 /*
  177  * exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package
  178  */
  179 
  180 int
  181 exec_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
  182 {
  183         struct exec *execp = epp->ep_hdr;
  184         long dsize, bsize, baddr;
  185 
  186         epp->ep_taddr = AOUT_LDPGSZ;
  187         epp->ep_tsize = execp->a_text;
  188         epp->ep_daddr = epp->ep_taddr + execp->a_text;
  189         epp->ep_dsize = execp->a_data + execp->a_bss;
  190         epp->ep_entry = execp->a_entry;
  191 
  192         /* set up command for text and data segments */
  193         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
  194             execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
  195             sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  196 
  197         /* set up command for bss segment */
  198         baddr = round_page(epp->ep_daddr + execp->a_data);
  199         bsize = epp->ep_daddr + epp->ep_dsize - baddr;
  200         if (bsize > 0)
  201                 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
  202                     NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  203 
  204         /*
  205          * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
  206          * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
  207          * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
  208          * respectively to page boundaries.
  209          * Compensate `ep_dsize' for the amount of data covered by the last
  210          * text page.
  211          */
  212         dsize = epp->ep_dsize + execp->a_text - round_page(execp->a_text);
  213         epp->ep_dsize = (dsize > 0) ? dsize : 0;
  214         return (*epp->ep_esch->es_setup_stack)(l, epp);
  215 }

Cache object: 03e7df2ba092f34f4f21347e477bcec3


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.