1 /* $NetBSD: procfs_subr.c,v 1.114 2019/09/26 17:34:08 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Andrew Doran. 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * This code is derived from software contributed to Berkeley by 37 * Jan-Simon Pendry. 38 * 39 * Redistribution and use in source and binary forms, with or without 40 * modification, are permitted provided that the following conditions 41 * are met: 42 * 1. Redistributions of source code must retain the above copyright 43 * notice, this list of conditions and the following disclaimer. 44 * 2. Redistributions in binary form must reproduce the above copyright 45 * notice, this list of conditions and the following disclaimer in the 46 * documentation and/or other materials provided with the distribution. 47 * 3. Neither the name of the University nor the names of its contributors 48 * may be used to endorse or promote products derived from this software 49 * without specific prior written permission. 50 * 51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 * 63 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95 64 */ 65 66 /* 67 * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved. 68 * Copyright (c) 1993 Jan-Simon Pendry 69 * 70 * This code is derived from software contributed to Berkeley by 71 * Jan-Simon Pendry. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95 102 */ 103 104 #include <sys/cdefs.h> 105 __KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.114 2019/09/26 17:34:08 christos Exp $"); 106 107 #include <sys/param.h> 108 #include <sys/systm.h> 109 #include <sys/time.h> 110 #include <sys/kernel.h> 111 #include <sys/proc.h> 112 #include <sys/fstrans.h> 113 #include <sys/vnode.h> 114 #include <sys/stat.h> 115 #include <sys/file.h> 116 #include <sys/filedesc.h> 117 #include <sys/kauth.h> 118 #include <sys/sysctl.h> 119 120 #include <miscfs/procfs/procfs.h> 121 122 /* 123 * Allocate a pfsnode/vnode pair. The vnode is referenced. 124 * The pid, type, and file descriptor uniquely identify a pfsnode. 125 */ 126 int 127 procfs_allocvp(struct mount *mp, struct vnode **vpp, pid_t pid, 128 pfstype type, int fd) 129 { 130 struct pfskey key; 131 132 memset(&key, 0, sizeof(key)); 133 key.pk_type = type; 134 key.pk_pid = pid; 135 key.pk_fd = fd; 136 137 return vcache_get(mp, &key, sizeof(key), vpp); 138 } 139 140 int 141 procfs_rw(void *v) 142 { 143 struct vop_read_args *ap = v; 144 struct vnode *vp = ap->a_vp; 145 struct uio *uio = ap->a_uio; 146 struct lwp *curl; 147 struct lwp *l; 148 struct pfsnode *pfs = VTOPFS(vp); 149 struct proc *p; 150 int error; 151 152 if (uio->uio_offset < 0) 153 return EINVAL; 154 155 if ((error = procfs_proc_lock(pfs->pfs_pid, &p, ESRCH)) != 0) 156 return error; 157 158 curl = curlwp; 159 160 /* 161 * Do not allow init to be modified while in secure mode; it 162 * could be duped into changing the security level. 163 */ 164 #define M2K(m) ((m) == UIO_READ ? KAUTH_REQ_PROCESS_PROCFS_READ : \ 165 KAUTH_REQ_PROCESS_PROCFS_WRITE) 166 mutex_enter(p->p_lock); 167 error = kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_PROCFS, 168 p, pfs, KAUTH_ARG(M2K(uio->uio_rw)), NULL); 169 mutex_exit(p->p_lock); 170 if (error) { 171 procfs_proc_unlock(p); 172 return (error); 173 } 174 #undef M2K 175 176 mutex_enter(p->p_lock); 177 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 178 if (l->l_stat != LSZOMB) 179 break; 180 } 181 /* Process is exiting if no-LWPS or all LWPs are LSZOMB */ 182 if (l == NULL) { 183 mutex_exit(p->p_lock); 184 procfs_proc_unlock(p); 185 return ESRCH; 186 } 187 188 lwp_addref(l); 189 mutex_exit(p->p_lock); 190 191 switch (pfs->pfs_type) { 192 case PFSnote: 193 case PFSnotepg: 194 error = procfs_donote(curl, p, pfs, uio); 195 break; 196 197 case PFSregs: 198 error = procfs_doregs(curl, l, pfs, uio); 199 break; 200 201 case PFSfpregs: 202 error = procfs_dofpregs(curl, l, pfs, uio); 203 break; 204 205 case PFSstatus: 206 error = procfs_dostatus(curl, l, pfs, uio); 207 break; 208 209 case PFSstat: 210 error = procfs_do_pid_stat(curl, l, pfs, uio); 211 break; 212 213 case PFSlimit: 214 error = procfs_dolimit(curl, p, pfs, uio); 215 break; 216 217 case PFSmap: 218 error = procfs_domap(curl, p, pfs, uio, 0); 219 break; 220 221 case PFSmaps: 222 error = procfs_domap(curl, p, pfs, uio, 1); 223 break; 224 225 case PFSmem: 226 error = procfs_domem(curl, l, pfs, uio); 227 break; 228 229 case PFScmdline: 230 error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ARGV); 231 break; 232 233 case PFSenviron: 234 error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ENV); 235 break; 236 237 case PFSmeminfo: 238 error = procfs_domeminfo(curl, p, pfs, uio); 239 break; 240 241 case PFSdevices: 242 error = procfs_dodevices(curl, p, pfs, uio); 243 break; 244 245 case PFScpuinfo: 246 error = procfs_docpuinfo(curl, p, pfs, uio); 247 break; 248 249 case PFScpustat: 250 error = procfs_docpustat(curl, p, pfs, uio); 251 break; 252 253 case PFSloadavg: 254 error = procfs_doloadavg(curl, p, pfs, uio); 255 break; 256 257 case PFSstatm: 258 error = procfs_do_pid_statm(curl, l, pfs, uio); 259 break; 260 261 case PFSfd: 262 error = procfs_dofd(curl, p, pfs, uio); 263 break; 264 265 case PFSuptime: 266 error = procfs_douptime(curl, p, pfs, uio); 267 break; 268 269 case PFSmounts: 270 error = procfs_domounts(curl, p, pfs, uio); 271 break; 272 273 case PFSemul: 274 error = procfs_doemul(curl, p, pfs, uio); 275 break; 276 277 case PFSversion: 278 error = procfs_doversion(curl, p, pfs, uio); 279 break; 280 281 case PFSauxv: 282 error = procfs_doauxv(curl, p, pfs, uio); 283 break; 284 285 #ifdef __HAVE_PROCFS_MACHDEP 286 PROCFS_MACHDEP_NODETYPE_CASES 287 error = procfs_machdep_rw(curl, l, pfs, uio); 288 break; 289 #endif 290 291 default: 292 error = EOPNOTSUPP; 293 break; 294 } 295 296 /* 297 * Release the references that we acquired earlier. 298 */ 299 lwp_delref(l); 300 procfs_proc_unlock(p); 301 302 return (error); 303 } 304 305 /* 306 * Get a string from userland into (bf). Strip a trailing 307 * nl character (to allow easy access from the shell). 308 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 309 * will automatically add a nul char at the end. 310 * 311 * Returns 0 on success or the following errors 312 * 313 * EINVAL: file offset is non-zero. 314 * EMSGSIZE: message is longer than kernel buffer 315 * EFAULT: user i/o buffer is not addressable 316 */ 317 int 318 vfs_getuserstr(struct uio *uio, char *bf, int *buflenp) 319 { 320 size_t xlen; 321 int error; 322 323 if (uio->uio_offset != 0) 324 return (EINVAL); 325 326 xlen = *buflenp; 327 328 /* must be able to read the whole string in one go */ 329 if (xlen < uio->uio_resid) 330 return (EMSGSIZE); 331 xlen = uio->uio_resid; 332 333 if ((error = uiomove(bf, xlen, uio)) != 0) 334 return (error); 335 336 /* allow multiple writes without seeks */ 337 uio->uio_offset = 0; 338 339 /* cleanup string and remove trailing newline */ 340 bf[xlen] = '\0'; 341 xlen = strlen(bf); 342 if (xlen > 0 && bf[xlen-1] == '\n') 343 bf[--xlen] = '\0'; 344 *buflenp = xlen; 345 346 return (0); 347 } 348 349 const vfs_namemap_t * 350 vfs_findname(const vfs_namemap_t *nm, const char *bf, int buflen) 351 { 352 353 for (; nm->nm_name; nm++) 354 if (memcmp(bf, nm->nm_name, buflen+1) == 0) 355 return (nm); 356 357 return (0); 358 } 359 360 static bool 361 procfs_revoke_selector(void *arg, struct vnode *vp) 362 { 363 struct proc *p = arg; 364 struct pfsnode *pfs; 365 366 KASSERT(mutex_owned(vp->v_interlock)); 367 368 pfs = VTOPFS(vp); 369 370 return (pfs != NULL && pfs->pfs_pid == p->p_pid); 371 } 372 373 void 374 procfs_revoke_vnodes(struct proc *p, void *arg) 375 { 376 int error; 377 bool suspended; 378 struct vnode *vp; 379 struct vnode_iterator *marker; 380 struct mount *mp = (struct mount *)arg; 381 382 if (!(p->p_flag & PK_SUGID)) 383 return; 384 385 suspended = false; 386 vfs_vnode_iterator_init(mp, &marker); 387 388 while ((vp = vfs_vnode_iterator_next(marker, 389 procfs_revoke_selector, p)) != NULL) { 390 if (vrecycle(vp)) 391 continue; 392 /* Vnode is busy, we have to suspend the mount for vgone(). */ 393 while (! suspended) { 394 error = vfs_suspend(mp, 0); 395 if (error == 0) { 396 suspended = true; 397 } else if (error != EINTR && error != ERESTART) { 398 KASSERT(error == EOPNOTSUPP); 399 break; 400 } 401 } 402 vgone(vp); 403 } 404 405 if (suspended) 406 vfs_resume(mp); 407 408 vfs_vnode_iterator_destroy(marker); 409 } 410 411 int 412 procfs_proc_lock(int pid, struct proc **bunghole, int notfound) 413 { 414 struct proc *tp; 415 int error = 0; 416 417 mutex_enter(proc_lock); 418 419 if (pid == 0) 420 tp = &proc0; 421 else if ((tp = proc_find(pid)) == NULL) 422 error = notfound; 423 if (tp != NULL && !rw_tryenter(&tp->p_reflock, RW_READER)) 424 error = EBUSY; 425 426 mutex_exit(proc_lock); 427 428 *bunghole = tp; 429 return error; 430 } 431 432 void 433 procfs_proc_unlock(struct proc *p) 434 { 435 436 rw_exit(&p->p_reflock); 437 } 438 439 int 440 procfs_doemul(struct lwp *curl, struct proc *p, 441 struct pfsnode *pfs, struct uio *uio) 442 { 443 const char *ename = p->p_emul->e_name; 444 return uiomove_frombuf(__UNCONST(ename), strlen(ename), uio); 445 } 446