xref: /netbsd-src/sys/compat/common/compat_exec.c (revision 76c7fc5f6b13ed0b1508e6b313e88e59977ed78e)
1 /*	$NetBSD: compat_exec.c,v 1.18 2019/01/27 02:08:39 pgoyette 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: compat_exec.c,v 1.18 2019/01/27 02:08:39 pgoyette Exp $");
35 
36 #ifdef _KERNEL_OPT
37 #include "opt_compat_netbsd.h"
38 #include "opt_execfmt.h"
39 #endif
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/proc.h>
44 #include <sys/vnode.h>
45 #include <sys/exec.h>
46 #include <sys/resourcevar.h>
47 
48 #ifdef EXEC_AOUT
49 #include <sys/exec_aout.h>
50 
51 /*
52  * exec_aout_prep_oldzmagic():
53  *	Prepare the vmcmds to build a vmspace for an old ZMAGIC
54  *	binary. [386BSD/BSDI/4.4BSD/NetBSD0.8]
55  *
56  * Cloned from exec_aout_prep_zmagic() in kern/exec_aout.c; a more verbose
57  * description of operation is there.
58  * There were copies of this in the mac68k, hp300, and i386 ports.
59  */
60 int
61 exec_aout_prep_oldzmagic(struct lwp *l, struct exec_package *epp)
62 {
63 	struct exec *execp = epp->ep_hdr;
64 	int error;
65 
66 	epp->ep_taddr = 0;
67 	epp->ep_tsize = execp->a_text;
68 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
69 	epp->ep_dsize = execp->a_data + execp->a_bss;
70 	epp->ep_entry = execp->a_entry;
71 
72 	error = vn_marktext(epp->ep_vp);
73 	if (error)
74 		return (error);
75 
76 	/* set up command for text segment */
77 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
78 	    epp->ep_taddr, epp->ep_vp, PAGE_SIZE, /* XXX CLBYTES? */
79 	    VM_PROT_READ|VM_PROT_EXECUTE);
80 
81 	/* set up command for data segment */
82 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
83 	    epp->ep_daddr, epp->ep_vp,
84 	    execp->a_text + PAGE_SIZE, /* XXX CLBYTES? */
85 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
86 
87 	/* set up command for bss segment */
88 	if (execp->a_bss)
89 	    NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
90 		epp->ep_daddr + execp->a_data, NULLVP, 0,
91 		VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
92 
93 	return (*epp->ep_esch->es_setup_stack)(l, epp);
94 }
95 
96 
97 /*
98  * exec_aout_prep_oldnmagic():
99  *	Prepare the vmcmds to build a vmspace for an old NMAGIC
100  *	binary. [BSDI]
101  *
102  * Cloned from exec_aout_prep_nmagic() in kern/exec_aout.c; with text starting
103  * at 0.
104  * XXX: There must be a better way to share this code.
105  */
106 int
107 exec_aout_prep_oldnmagic(struct lwp *l, struct exec_package *epp)
108 {
109 	struct exec *execp = epp->ep_hdr;
110 	long bsize, baddr;
111 
112 	epp->ep_taddr = 0;
113 	epp->ep_tsize = execp->a_text;
114 	epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, AOUT_LDPGSZ);
115 	epp->ep_dsize = execp->a_data + execp->a_bss;
116 	epp->ep_entry = execp->a_entry;
117 
118 	/* set up command for text segment */
119 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
120 	    epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
121 	    VM_PROT_READ|VM_PROT_EXECUTE);
122 
123 	/* set up command for data segment */
124 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
125 	    epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
126 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
127 
128 	/* set up command for bss segment */
129 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
130 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
131 	if (bsize > 0)
132 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
133 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
134 
135 	return (*epp->ep_esch->es_setup_stack)(l, epp);
136 }
137 
138 
139 /*
140  * exec_aout_prep_oldomagic():
141  *	Prepare the vmcmds to build a vmspace for an old OMAGIC
142  *	binary. [BSDI]
143  *
144  * Cloned from exec_aout_prep_omagic() in kern/exec_aout.c; with text starting
145  * at 0.
146  * XXX: There must be a better way to share this code.
147  */
148 int
149 exec_aout_prep_oldomagic(struct lwp *l, struct exec_package *epp)
150 {
151 	struct exec *execp = epp->ep_hdr;
152 	long dsize, bsize, baddr;
153 
154 	epp->ep_taddr = 0;
155 	epp->ep_tsize = execp->a_text;
156 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
157 	epp->ep_dsize = execp->a_data + execp->a_bss;
158 	epp->ep_entry = execp->a_entry;
159 
160 	/* set up command for text and data segments */
161 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
162 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
163 	    sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
164 
165 	/* set up command for bss segment */
166 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
167 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
168 	if (bsize > 0)
169 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
170 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
171 
172 	/*
173 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
174 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
175 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
176 	 * respectively to page boundaries.
177 	 * Compensate `ep_dsize' for the amount of data covered by the last
178 	 * text page.
179 	 */
180 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
181 							PAGE_SIZE);
182 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
183 	return (*epp->ep_esch->es_setup_stack)(l, epp);
184 }
185 #endif /* EXEC_AOUT */
186