1 /* $NetBSD: procfs_subr.c,v 1.116 2020/05/23 23:42:43 ad 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 1.116 2020/05/23 23:42:43 ad 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 = 156 procfs_proc_lock(vp->v_mount, pfs->pfs_pid, &p, ESRCH)) != 0) 157 return error; 158 159 curl = curlwp; 160 161 /* 162 * Do not allow init to be modified while in secure mode; it 163 * could be duped into changing the security level. 164 */ 165 #define M2K(m) ((m) == UIO_READ ? KAUTH_REQ_PROCESS_PROCFS_READ : \ 166 KAUTH_REQ_PROCESS_PROCFS_WRITE) 167 mutex_enter(p->p_lock); 168 error = kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_PROCFS, 169 p, pfs, KAUTH_ARG(M2K(uio->uio_rw)), NULL); 170 mutex_exit(p->p_lock); 171 if (error) { 172 procfs_proc_unlock(p); 173 return (error); 174 } 175 #undef M2K 176 177 mutex_enter(p->p_lock); 178 LIST_FOREACH(l, &p->p_lwps, l_sibling) { 179 if (l->l_stat != LSZOMB) 180 break; 181 } 182 /* Process is exiting if no-LWPS or all LWPs are LSZOMB */ 183 if (l == NULL) { 184 mutex_exit(p->p_lock); 185 procfs_proc_unlock(p); 186 return ESRCH; 187 } 188 189 lwp_addref(l); 190 mutex_exit(p->p_lock); 191 192 switch (pfs->pfs_type) { 193 case PFSnote: 194 case PFSnotepg: 195 error = procfs_donote(curl, p, pfs, uio); 196 break; 197 198 case PFSregs: 199 error = procfs_doregs(curl, l, pfs, uio); 200 break; 201 202 case PFSfpregs: 203 error = procfs_dofpregs(curl, l, pfs, uio); 204 break; 205 206 case PFSstatus: 207 error = procfs_dostatus(curl, l, pfs, uio); 208 break; 209 210 case PFSstat: 211 error = procfs_do_pid_stat(curl, l, pfs, uio); 212 break; 213 214 case PFSlimit: 215 error = procfs_dolimit(curl, p, pfs, uio); 216 break; 217 218 case PFSmap: 219 error = procfs_domap(curl, p, pfs, uio, 0); 220 break; 221 222 case PFSmaps: 223 error = procfs_domap(curl, p, pfs, uio, 1); 224 break; 225 226 case PFSmem: 227 error = procfs_domem(curl, l, pfs, uio); 228 break; 229 230 case PFScmdline: 231 error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ARGV); 232 break; 233 234 case PFSenviron: 235 error = procfs_doprocargs(curl, p, pfs, uio, KERN_PROC_ENV); 236 break; 237 238 case PFSmeminfo: 239 error = procfs_domeminfo(curl, p, pfs, uio); 240 break; 241 242 case PFSdevices: 243 error = procfs_dodevices(curl, p, pfs, uio); 244 break; 245 246 case PFScpuinfo: 247 error = procfs_docpuinfo(curl, p, pfs, uio); 248 break; 249 250 case PFScpustat: 251 error = procfs_docpustat(curl, p, pfs, uio); 252 break; 253 254 case PFSloadavg: 255 error = procfs_doloadavg(curl, p, pfs, uio); 256 break; 257 258 case PFSstatm: 259 error = procfs_do_pid_statm(curl, l, pfs, uio); 260 break; 261 262 case PFSfd: 263 error = procfs_dofd(curl, p, pfs, uio); 264 break; 265 266 case PFSuptime: 267 error = procfs_douptime(curl, p, pfs, uio); 268 break; 269 270 case PFSmounts: 271 error = procfs_domounts(curl, p, pfs, uio); 272 break; 273 274 case PFSemul: 275 error = procfs_doemul(curl, p, pfs, uio); 276 break; 277 278 case PFSversion: 279 error = procfs_doversion(curl, p, pfs, uio); 280 break; 281 282 case PFSauxv: 283 error = procfs_doauxv(curl, p, pfs, uio); 284 break; 285 286 #ifdef __HAVE_PROCFS_MACHDEP 287 PROCFS_MACHDEP_NODETYPE_CASES 288 error = procfs_machdep_rw(curl, l, pfs, uio); 289 break; 290 #endif 291 292 default: 293 error = EOPNOTSUPP; 294 break; 295 } 296 297 /* 298 * Release the references that we acquired earlier. 299 */ 300 lwp_delref(l); 301 procfs_proc_unlock(p); 302 303 return (error); 304 } 305 306 /* 307 * Get a string from userland into (bf). Strip a trailing 308 * nl character (to allow easy access from the shell). 309 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 310 * will automatically add a nul char at the end. 311 * 312 * Returns 0 on success or the following errors 313 * 314 * EINVAL: file offset is non-zero. 315 * EMSGSIZE: message is longer than kernel buffer 316 * EFAULT: user i/o buffer is not addressable 317 */ 318 int 319 vfs_getuserstr(struct uio *uio, char *bf, int *buflenp) 320 { 321 size_t xlen; 322 int error; 323 324 if (uio->uio_offset != 0) 325 return (EINVAL); 326 327 xlen = *buflenp; 328 329 /* must be able to read the whole string in one go */ 330 if (xlen < uio->uio_resid) 331 return (EMSGSIZE); 332 xlen = uio->uio_resid; 333 334 if ((error = uiomove(bf, xlen, uio)) != 0) 335 return (error); 336 337 /* allow multiple writes without seeks */ 338 uio->uio_offset = 0; 339 340 /* cleanup string and remove trailing newline */ 341 bf[xlen] = '\0'; 342 xlen = strlen(bf); 343 if (xlen > 0 && bf[xlen-1] == '\n') 344 bf[--xlen] = '\0'; 345 *buflenp = xlen; 346 347 return (0); 348 } 349 350 const vfs_namemap_t * 351 vfs_findname(const vfs_namemap_t *nm, const char *bf, int buflen) 352 { 353 354 for (; nm->nm_name; nm++) 355 if (memcmp(bf, nm->nm_name, buflen+1) == 0) 356 return (nm); 357 358 return (0); 359 } 360 361 static bool 362 procfs_revoke_selector(void *arg, struct vnode *vp) 363 { 364 struct proc *p = arg; 365 struct pfsnode *pfs; 366 367 KASSERT(mutex_owned(vp->v_interlock)); 368 369 pfs = VTOPFS(vp); 370 371 return (pfs != NULL && pfs->pfs_pid == p->p_pid); 372 } 373 374 void 375 procfs_revoke_vnodes(struct proc *p, void *arg) 376 { 377 int error; 378 bool suspended; 379 struct vnode *vp; 380 struct vnode_iterator *marker; 381 struct mount *mp = (struct mount *)arg; 382 383 if (!(p->p_flag & PK_SUGID)) 384 return; 385 386 suspended = false; 387 vfs_vnode_iterator_init(mp, &marker); 388 389 while ((vp = vfs_vnode_iterator_next(marker, 390 procfs_revoke_selector, p)) != NULL) { 391 if (vrecycle(vp)) 392 continue; 393 /* Vnode is busy, we have to suspend the mount for vgone(). */ 394 while (! suspended) { 395 error = vfs_suspend(mp, 0); 396 if (error == 0) { 397 suspended = true; 398 } else if (error != EINTR && error != ERESTART) { 399 KASSERT(error == EOPNOTSUPP); 400 break; 401 } 402 } 403 vgone(vp); 404 } 405 406 if (suspended) 407 vfs_resume(mp); 408 409 vfs_vnode_iterator_destroy(marker); 410 } 411 412 bool 413 procfs_use_linux_compat(struct mount *mp) 414 { 415 const int flags = VFSTOPROC(mp)->pmnt_flags; 416 417 return (flags & PROCFSMNT_LINUXCOMPAT) ? true : false; 418 } 419 420 struct proc * 421 procfs_proc_find(struct mount *mp, pid_t pid) 422 { 423 424 KASSERT(mutex_owned(&proc_lock)); 425 return procfs_use_linux_compat(mp) ? proc_find_lwpid(pid) 426 : proc_find(pid); 427 } 428 429 int 430 procfs_proc_lock(struct mount *mp, int pid, struct proc **bunghole, 431 int notfound) 432 { 433 struct proc *tp; 434 int error = 0; 435 436 mutex_enter(&proc_lock); 437 438 if (pid == 0) 439 tp = &proc0; 440 else if ((tp = procfs_proc_find(mp, pid)) == NULL) 441 error = notfound; 442 if (tp != NULL && !rw_tryenter(&tp->p_reflock, RW_READER)) 443 error = EBUSY; 444 445 mutex_exit(&proc_lock); 446 447 *bunghole = tp; 448 return error; 449 } 450 451 void 452 procfs_proc_unlock(struct proc *p) 453 { 454 455 rw_exit(&p->p_reflock); 456 } 457 458 int 459 procfs_doemul(struct lwp *curl, struct proc *p, 460 struct pfsnode *pfs, struct uio *uio) 461 { 462 const char *ename = p->p_emul->e_name; 463 return uiomove_frombuf(__UNCONST(ename), strlen(ename), uio); 464 } 465