1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
/* $OpenBSD: exec_aout.c,v 1.7 2001/11/15 06:22:30 art Exp $ */
/* $NetBSD: exec_aout.c,v 1.14 1996/02/04 02:15:01 christos Exp $ */
/*
* Copyright (c) 1993, 1994 Christopher G. Demetriou
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/exec.h>
#include <sys/resourcevar.h>
#include <uvm/uvm_extern.h>
#if defined(_KERN_DO_AOUT)
/*
* exec_aout_makecmds(): Check if it's an a.out-format executable.
*
* Given a proc pointer and an exec package pointer, see if the referent
* of the epp is in a.out format. First check 'standard' magic numbers for
* this architecture. If that fails, try a cpu-dependent hook.
*
* This function, in the former case, or the hook, in the latter, is
* responsible for creating a set of vmcmds which can be used to build
* the process's vm space and inserting them into the exec package.
*/
int
exec_aout_makecmds(p, epp)
struct proc *p;
struct exec_package *epp;
{
u_long midmag, magic;
u_short mid;
int error;
struct exec *execp = epp->ep_hdr;
if (epp->ep_hdrvalid < sizeof(struct exec))
return ENOEXEC;
midmag = ntohl(execp->a_midmag);
mid = (midmag >> 16) & 0x3ff;
magic = midmag & 0xffff;
midmag = mid << 16 | magic;
switch (midmag) {
case (MID_MACHINE << 16) | ZMAGIC:
error = exec_aout_prep_zmagic(p, epp);
break;
case (MID_MACHINE << 16) | NMAGIC:
error = exec_aout_prep_nmagic(p, epp);
break;
case (MID_MACHINE << 16) | OMAGIC:
error = exec_aout_prep_omagic(p, epp);
break;
default:
error = cpu_exec_aout_makecmds(p, epp);
}
if (error)
kill_vmcmds(&epp->ep_vmcmds);
return error;
}
/*
* exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package
*
* First, set of the various offsets/lengths in the exec package.
*
* Then, mark the text image busy (so it can be demand paged) or error
* out if this is not possible. Finally, set up vmcmds for the
* text, data, bss, and stack segments.
*/
int
exec_aout_prep_zmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = epp->ep_taddr + execp->a_text;
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/*
* check if vnode is in open for writing, because we want to
* demand-page out of it. if it is, don't do it, for various
* reasons
*/
if ((execp->a_text != 0 || execp->a_data != 0) &&
epp->ep_vp->v_writecount != 0) {
#ifdef DIAGNOSTIC
if (epp->ep_vp->v_flag & VTEXT)
panic("exec: a VTEXT vnode has writecount != 0");
#endif
return ETXTBSY;
}
vn_marktext(epp->ep_vp);
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, execp->a_text,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
epp->ep_daddr + execp->a_data, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return exec_setup_stack(p, epp);
}
/*
* exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package
*/
int
exec_aout_prep_nmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
long bsize, baddr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, __LDPGSZ);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = round_page(epp->ep_daddr + execp->a_data);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return exec_setup_stack(p, epp);
}
/*
* exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package
*/
int
exec_aout_prep_omagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
long dsize, bsize, baddr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = epp->ep_taddr + execp->a_text;
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text and data segments */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = round_page(epp->ep_daddr + execp->a_data);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/*
* Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
* obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
* computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
* respectively to page boundaries.
* Compensate `ep_dsize' for the amount of data covered by the last
* text page.
*/
dsize = epp->ep_dsize + execp->a_text - round_page(execp->a_text);
epp->ep_dsize = (dsize > 0) ? dsize : 0;
return exec_setup_stack(p, epp);
}
#endif /* _KERN_DO_AOUT */
|