2 * Copyright (c) 1993, David Greenman
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
32 #include <sys/imgact.h>
33 #include <sys/imgact_aout.h>
34 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/mutex.h>
39 #include <sys/resourcevar.h>
40 #include <sys/signalvar.h>
41 #include <sys/syscall.h>
42 #include <sys/sysent.h>
43 #include <sys/systm.h>
44 #include <sys/vnode.h>
46 #include <machine/frame.h>
47 #include <machine/md_var.h>
51 #include <vm/vm_map.h>
52 #include <vm/vm_object.h>
53 #include <vm/vm_param.h>
55 static int exec_aout_imgact(struct image_params *imgp);
56 static int aout_fixup(register_t **stack_base, struct image_params *imgp);
58 struct sysentvec aout_sysvec = {
59 .sv_size = SYS_MAXSYSCALL,
67 .sv_fixup = aout_fixup,
68 .sv_sendsig = sendsig,
69 .sv_sigcode = sigcode,
70 .sv_szsigcode = &szsigcode,
71 .sv_prepsyscall = NULL,
72 .sv_name = "FreeBSD a.out",
74 .sv_imgact_try = NULL,
75 .sv_minsigstksz = MINSIGSTKSZ,
76 .sv_pagesize = PAGE_SIZE,
77 .sv_minuser = VM_MIN_ADDRESS,
78 .sv_maxuser = VM_MAXUSER_ADDRESS,
79 .sv_usrstack = USRSTACK,
80 .sv_psstrings = PS_STRINGS,
81 .sv_stackprot = VM_PROT_ALL,
82 .sv_copyout_strings = exec_copyout_strings,
83 .sv_setregs = exec_setregs,
89 aout_fixup(stack_base, imgp)
90 register_t **stack_base;
91 struct image_params *imgp;
94 return (suword(--(*stack_base), imgp->args->argc));
98 exec_aout_imgact(imgp)
99 struct image_params *imgp;
101 const struct exec *a_out = (const struct exec *) imgp->image_header;
102 struct vmspace *vmspace;
105 vm_offset_t text_end, data_end;
106 unsigned long virtual_offset;
107 unsigned long file_offset;
108 unsigned long bss_size;
112 * Linux and *BSD binaries look very much alike,
113 * only the machine id is different:
114 * 0x64 for Linux, 0x86 for *BSD, 0x00 for BSDI.
115 * NetBSD is in network byte order.. ugh.
117 if (((a_out->a_magic >> 16) & 0xff) != 0x86 &&
118 ((a_out->a_magic >> 16) & 0xff) != 0 &&
119 ((((int)ntohl(a_out->a_magic)) >> 16) & 0xff) != 0x86)
123 * Set file/virtual offset based on a.out variant.
124 * We do two cases: host byte order and network byte order
125 * (for NetBSD compatibility)
127 switch ((int)(a_out->a_magic & 0xffff)) {
131 file_offset = PAGE_SIZE;
133 /* Bill's "screwball mode" */
138 virtual_offset = PAGE_SIZE;
140 /* Pass PS_STRINGS for BSD/OS binaries only. */
141 if (N_GETMID(*a_out) == MID_ZERO)
142 imgp->ps_strings = aout_sysvec.sv_psstrings;
145 /* NetBSD compatibility */
146 switch ((int)(ntohl(a_out->a_magic) & 0xffff)) {
149 virtual_offset = PAGE_SIZE;
157 bss_size = roundup(a_out->a_bss, PAGE_SIZE);
160 * Check various fields in header for validity/bounds.
162 if (/* entry point must lay with text region */
163 a_out->a_entry < virtual_offset ||
164 a_out->a_entry >= virtual_offset + a_out->a_text ||
166 /* text and data size must each be page rounded */
167 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK)
170 /* text + data can't exceed file size */
171 if (a_out->a_data + a_out->a_text > imgp->attr->va_size)
175 * text/data/bss must not exceed limits
177 PROC_LOCK(imgp->proc);
178 if (/* text can't exceed maximum text size */
179 a_out->a_text > maxtsiz ||
181 /* data + bss can't exceed rlimit */
182 a_out->a_data + bss_size > lim_cur(imgp->proc, RLIMIT_DATA)) {
183 PROC_UNLOCK(imgp->proc);
186 PROC_UNLOCK(imgp->proc);
189 * Avoid a possible deadlock if the current address space is destroyed
190 * and that address space maps the locked vnode. In the common case,
191 * the locked vnode's v_usecount is decremented but remains greater
192 * than zero. Consequently, the vnode lock is not needed by vrele().
193 * However, in cases where the vnode lock is external, such as nullfs,
194 * v_usecount may become zero.
196 VOP_UNLOCK(imgp->vp, 0);
199 * Destroy old process VM and create a new one (with a new stack)
201 error = exec_new_vmspace(imgp, &aout_sysvec);
203 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
208 * The vm space can be changed by exec_new_vmspace
210 vmspace = imgp->proc->p_vmspace;
212 object = imgp->object;
213 map = &vmspace->vm_map;
215 vm_object_reference(object);
217 text_end = virtual_offset + a_out->a_text;
218 error = vm_map_insert(map, object,
220 virtual_offset, text_end,
221 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL,
222 MAP_COPY_ON_WRITE | MAP_PREFAULT);
225 vm_object_deallocate(object);
228 data_end = text_end + a_out->a_data;
230 vm_object_reference(object);
231 error = vm_map_insert(map, object,
232 file_offset + a_out->a_text,
234 VM_PROT_ALL, VM_PROT_ALL,
235 MAP_COPY_ON_WRITE | MAP_PREFAULT);
238 vm_object_deallocate(object);
244 error = vm_map_insert(map, NULL, 0,
245 data_end, data_end + bss_size,
246 VM_PROT_ALL, VM_PROT_ALL, 0);
254 /* Fill in process VM information */
255 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT;
256 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT;
257 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset;
258 vmspace->vm_daddr = (caddr_t) (uintptr_t)
259 (virtual_offset + a_out->a_text);
261 /* Fill in image_params */
262 imgp->interpreted = 0;
263 imgp->entry_addr = a_out->a_entry;
265 imgp->proc->p_sysent = &aout_sysvec;
271 * Tell kern_execve.c about it, with a little help from the linker.
273 static struct execsw aout_execsw = { exec_aout_imgact, "a.out" };
274 EXEC_SET(aout, aout_execsw);