xref: /netbsd-src/sys/miscfs/procfs/procfs_map.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: procfs_map.c,v 1.33 2007/11/26 19:02:16 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Jan-Simon Pendry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)procfs_status.c	8.3 (Berkeley) 2/17/94
35  *
36  *	$FreeBSD: procfs_map.c,v 1.18 1998/12/04 22:54:51 archie Exp $
37  */
38 
39 /*
40  * Copyright (c) 1993 Jan-Simon Pendry
41  *
42  * This code is derived from software contributed to Berkeley by
43  * Jan-Simon Pendry.
44  *
45  * Redistribution and use in source and binary forms, with or without
46  * modification, are permitted provided that the following conditions
47  * are met:
48  * 1. Redistributions of source code must retain the above copyright
49  *    notice, this list of conditions and the following disclaimer.
50  * 2. Redistributions in binary form must reproduce the above copyright
51  *    notice, this list of conditions and the following disclaimer in the
52  *    documentation and/or other materials provided with the distribution.
53  * 3. All advertising materials mentioning features or use of this software
54  *    must display the following acknowledgement:
55  *	This product includes software developed by the University of
56  *	California, Berkeley and its contributors.
57  * 4. Neither the name of the University nor the names of its contributors
58  *    may be used to endorse or promote products derived from this software
59  *    without specific prior written permission.
60  *
61  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
62  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
65  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71  * SUCH DAMAGE.
72  *
73  *	@(#)procfs_status.c	8.3 (Berkeley) 2/17/94
74  *
75  *	$FreeBSD: procfs_map.c,v 1.18 1998/12/04 22:54:51 archie Exp $
76  */
77 
78 #include <sys/cdefs.h>
79 __KERNEL_RCSID(0, "$NetBSD: procfs_map.c,v 1.33 2007/11/26 19:02:16 pooka Exp $");
80 
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/proc.h>
84 #include <sys/vnode.h>
85 #include <sys/malloc.h>
86 #include <sys/namei.h>
87 #include <sys/filedesc.h>
88 #include <miscfs/procfs/procfs.h>
89 
90 #include <sys/lock.h>
91 
92 #include <uvm/uvm.h>
93 
94 #define BUFFERSIZE (64 * 1024)
95 
96 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
97 				struct lwp *curl, struct proc *p);
98 
99 /*
100  * The map entries can *almost* be read with programs like cat.  However,
101  * large maps need special programs to read.  It is not easy to implement
102  * a program that can sense the required size of the buffer, and then
103  * subsequently do a read with the appropriate size.  This operation cannot
104  * be atomic.  The best that we can do is to allow the program to do a read
105  * with an arbitrarily large buffer, and return as much as we can.  We can
106  * return an error code if the buffer is too small (EFBIG), then the program
107  * can try a bigger buffer.
108  */
109 int
110 procfs_domap(struct lwp *curl, struct proc *p, struct pfsnode *pfs,
111 	     struct uio *uio, int linuxmode)
112 {
113 	int error;
114 	struct vmspace *vm;
115 	struct vm_map *map;
116 	struct vm_map_entry *entry;
117 	char *buffer;
118 	char *path;
119 	struct vnode *vp;
120 	struct vattr va;
121 	dev_t dev;
122 	long fileid;
123 	size_t pos;
124 
125 	if (uio->uio_rw != UIO_READ)
126 		return EOPNOTSUPP;
127 
128 	if (uio->uio_offset != 0) {
129 		/*
130 		 * we return 0 here, so that the second read returns EOF
131 		 * we don't support reading from an offset because the
132 		 * map could have changed between the two reads.
133 		 */
134 		return 0;
135 	}
136 
137 	error = 0;
138 
139 	buffer = malloc(BUFFERSIZE, M_TEMP, M_WAITOK);
140 	if (linuxmode != 0)
141 		path = malloc(MAXPATHLEN * 4, M_TEMP, M_WAITOK);
142 	else
143 		path = NULL;
144 
145 	if ((error = proc_vmspace_getref(p, &vm)) != 0)
146 		goto out;
147 
148 	map = &vm->vm_map;
149 	vm_map_lock_read(map);
150 
151 	pos = 0;
152 	for (entry = map->header.next; entry != &map->header;
153 	    entry = entry->next) {
154 
155 		if (UVM_ET_ISSUBMAP(entry))
156 			continue;
157 
158 		if (linuxmode != 0) {
159 			*path = 0;
160 			dev = (dev_t)0;
161 			fileid = 0;
162 			if (UVM_ET_ISOBJ(entry) &&
163 			    UVM_OBJ_IS_VNODE(entry->object.uvm_obj)) {
164 				vp = (struct vnode *)entry->object.uvm_obj;
165 				error = VOP_GETATTR(vp, &va, curl->l_cred);
166 				if (error == 0 && vp != pfs->pfs_vnode) {
167 					fileid = va.va_fileid;
168 					dev = va.va_fsid;
169 					error = procfs_vnode_to_path(vp, path,
170 					    MAXPATHLEN * 4, curl, p);
171 				}
172 			}
173 			pos += snprintf(buffer + pos, BUFFERSIZE - pos,
174 			    "%0*lx-%0*lx %c%c%c%c %0*lx %02x:%02x %ld     %s\n",
175 			    (int)sizeof(void *) * 2,(unsigned long)entry->start,
176 			    (int)sizeof(void *) * 2,(unsigned long)entry->end,
177 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
178 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
179 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
180 			    (entry->etype & UVM_ET_COPYONWRITE) ? 'p' : 's',
181 			    (int)sizeof(void *) * 2,
182 			    (unsigned long)entry->offset,
183 			    major(dev), minor(dev), fileid, path);
184 		} else {
185 			pos += snprintf(buffer + pos, BUFFERSIZE - pos,
186 			    "0x%lx 0x%lx %c%c%c %c%c%c %s %s %d %d %d\n",
187 			    entry->start, entry->end,
188 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
189 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
190 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
191 			    (entry->max_protection & VM_PROT_READ) ? 'r' : '-',
192 			    (entry->max_protection & VM_PROT_WRITE) ? 'w' : '-',
193 			    (entry->max_protection & VM_PROT_EXECUTE) ?
194 				'x' : '-',
195 			    (entry->etype & UVM_ET_COPYONWRITE) ?
196 				"COW" : "NCOW",
197 			    (entry->etype & UVM_ET_NEEDSCOPY) ? "NC" : "NNC",
198 			    entry->inheritance, entry->wired_count,
199 			    entry->advice);
200 		}
201 	}
202 
203 	vm_map_unlock_read(map);
204 	uvmspace_free(vm);
205 
206 	error = uiomove(buffer, pos, uio);
207 out:
208 	if (path != NULL)
209 		free(path, M_TEMP);
210 	if (buffer != NULL)
211 		free(buffer, M_TEMP);
212 
213 	return error;
214 }
215 
216 int
217 procfs_validmap(struct lwp *l, struct mount *mp)
218 {
219 	return ((l->l_flag & LW_SYSTEM) == 0);
220 }
221 
222 /*
223  * Try to find a pathname for a vnode. Since there is no mapping
224  * vnode -> parent directory, this needs the NAMECACHE_ENTER_REVERSE
225  * option to work (to make cache_revlookup succeed).
226  */
227 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
228 				struct lwp *curl, struct proc *p)
229 {
230 	struct proc *curp = curl->l_proc;
231 	int error, lenused, elen;
232 	char *bp, *bend;
233 	struct vnode *dvp;
234 
235 	bp = bend = &path[len];
236 	*(--bp) = '\0';
237 
238 	error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
239 	if (error != 0)
240 		return error;
241 	error = cache_revlookup(vp, &dvp, &bp, path);
242 	vput(vp);
243 	if (error != 0)
244 		return (error == -1 ? ENOENT : error);
245 
246 	error = vget(dvp, 0);
247 	if (error != 0)
248 		return error;
249 	*(--bp) = '/';
250 	/* XXX GETCWD_CHECK_ACCESS == 0x0001 */
251 	error = getcwd_common(dvp, NULL, &bp, path, len / 2, 1, curl);
252 
253 	/*
254 	 * Strip off emulation path for emulated processes looking at
255 	 * the maps file of a process of the same emulation. (Won't
256 	 * work if /emul/xxx is a symlink..)
257 	 */
258 	if (curp->p_emul == p->p_emul && curp->p_emul->e_path != NULL) {
259 		elen = strlen(curp->p_emul->e_path);
260 		if (!strncmp(bp, curp->p_emul->e_path, elen))
261 			bp = &bp[elen];
262 	}
263 
264 	lenused = bend - bp;
265 
266 	memcpy(path, bp, lenused);
267 	path[lenused] = 0;
268 
269 	return 0;
270 }
271