1 /* $NetBSD: subr_copy.c,v 1.8 2018/05/28 21:04:41 chs Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 1998, 1999, 2002, 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 Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1991, 1993 35 * The Regents of the University of California. All rights reserved. 36 * (c) UNIX System Laboratories, Inc. 37 * All or some portions of this file are derived from material licensed 38 * to the University of California by American Telephone and Telegraph 39 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 40 * the permission of UNIX System Laboratories, Inc. 41 * 42 * Copyright (c) 1992, 1993 43 * The Regents of the University of California. All rights reserved. 44 * 45 * This software was developed by the Computer Systems Engineering group 46 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 47 * contributed to Berkeley. 48 * 49 * All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * This product includes software developed by the University of 52 * California, Lawrence Berkeley Laboratory. 53 * 54 * Redistribution and use in source and binary forms, with or without 55 * modification, are permitted provided that the following conditions 56 * are met: 57 * 1. Redistributions of source code must retain the above copyright 58 * notice, this list of conditions and the following disclaimer. 59 * 2. Redistributions in binary form must reproduce the above copyright 60 * notice, this list of conditions and the following disclaimer in the 61 * documentation and/or other materials provided with the distribution. 62 * 3. Neither the name of the University nor the names of its contributors 63 * may be used to endorse or promote products derived from this software 64 * without specific prior written permission. 65 * 66 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 67 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 68 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 69 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 70 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 71 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 72 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 73 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 74 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 75 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 76 * SUCH DAMAGE. 77 * 78 * @(#)kern_subr.c 8.4 (Berkeley) 2/14/95 79 */ 80 81 #include <sys/cdefs.h> 82 __KERNEL_RCSID(0, "$NetBSD: subr_copy.c,v 1.8 2018/05/28 21:04:41 chs Exp $"); 83 84 #include <sys/param.h> 85 #include <sys/fcntl.h> 86 #include <sys/proc.h> 87 #include <sys/systm.h> 88 89 #include <uvm/uvm_extern.h> 90 91 void 92 uio_setup_sysspace(struct uio *uio) 93 { 94 95 uio->uio_vmspace = vmspace_kernel(); 96 } 97 98 int 99 uiomove(void *buf, size_t n, struct uio *uio) 100 { 101 struct vmspace *vm = uio->uio_vmspace; 102 struct iovec *iov; 103 size_t cnt; 104 int error = 0; 105 char *cp = buf; 106 107 ASSERT_SLEEPABLE(); 108 109 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE); 110 while (n > 0 && uio->uio_resid) { 111 iov = uio->uio_iov; 112 cnt = iov->iov_len; 113 if (cnt == 0) { 114 KASSERT(uio->uio_iovcnt > 0); 115 uio->uio_iov++; 116 uio->uio_iovcnt--; 117 continue; 118 } 119 if (cnt > n) 120 cnt = n; 121 if (!VMSPACE_IS_KERNEL_P(vm)) { 122 if (curcpu()->ci_schedstate.spc_flags & 123 SPCF_SHOULDYIELD) 124 preempt(); 125 } 126 127 if (uio->uio_rw == UIO_READ) { 128 error = copyout_vmspace(vm, cp, iov->iov_base, 129 cnt); 130 } else { 131 error = copyin_vmspace(vm, iov->iov_base, cp, 132 cnt); 133 } 134 if (error) { 135 break; 136 } 137 iov->iov_base = (char *)iov->iov_base + cnt; 138 iov->iov_len -= cnt; 139 uio->uio_resid -= cnt; 140 uio->uio_offset += cnt; 141 cp += cnt; 142 KDASSERT(cnt <= n); 143 n -= cnt; 144 } 145 146 return (error); 147 } 148 149 /* 150 * Wrapper for uiomove() that validates the arguments against a known-good 151 * kernel buffer. 152 */ 153 int 154 uiomove_frombuf(void *buf, size_t buflen, struct uio *uio) 155 { 156 size_t offset; 157 158 if (uio->uio_offset < 0 || /* uio->uio_resid < 0 || */ 159 (offset = uio->uio_offset) != uio->uio_offset) 160 return (EINVAL); 161 if (offset >= buflen) 162 return (0); 163 return (uiomove((char *)buf + offset, buflen - offset, uio)); 164 } 165 166 /* 167 * Give next character to user as result of read. 168 */ 169 int 170 ureadc(int c, struct uio *uio) 171 { 172 struct iovec *iov; 173 174 if (uio->uio_resid <= 0) 175 panic("ureadc: non-positive resid"); 176 again: 177 if (uio->uio_iovcnt <= 0) 178 panic("ureadc: non-positive iovcnt"); 179 iov = uio->uio_iov; 180 if (iov->iov_len <= 0) { 181 uio->uio_iovcnt--; 182 uio->uio_iov++; 183 goto again; 184 } 185 if (!VMSPACE_IS_KERNEL_P(uio->uio_vmspace)) { 186 if (subyte(iov->iov_base, c) < 0) 187 return (EFAULT); 188 } else { 189 *(char *)iov->iov_base = c; 190 } 191 iov->iov_base = (char *)iov->iov_base + 1; 192 iov->iov_len--; 193 uio->uio_resid--; 194 uio->uio_offset++; 195 return (0); 196 } 197 198 /* 199 * Like copyin(), but operates on an arbitrary vmspace. 200 */ 201 int 202 copyin_vmspace(struct vmspace *vm, const void *uaddr, void *kaddr, size_t len) 203 { 204 struct iovec iov; 205 struct uio uio; 206 int error; 207 208 if (len == 0) 209 return (0); 210 211 if (VMSPACE_IS_KERNEL_P(vm)) { 212 return kcopy(uaddr, kaddr, len); 213 } 214 if (__predict_true(vm == curproc->p_vmspace)) { 215 return copyin(uaddr, kaddr, len); 216 } 217 218 iov.iov_base = kaddr; 219 iov.iov_len = len; 220 uio.uio_iov = &iov; 221 uio.uio_iovcnt = 1; 222 uio.uio_offset = (off_t)(uintptr_t)uaddr; 223 uio.uio_resid = len; 224 uio.uio_rw = UIO_READ; 225 UIO_SETUP_SYSSPACE(&uio); 226 error = uvm_io(&vm->vm_map, &uio, 0); 227 228 return (error); 229 } 230 231 /* 232 * Like copyout(), but operates on an arbitrary vmspace. 233 */ 234 int 235 copyout_vmspace(struct vmspace *vm, const void *kaddr, void *uaddr, size_t len) 236 { 237 struct iovec iov; 238 struct uio uio; 239 int error; 240 241 if (len == 0) 242 return (0); 243 244 if (VMSPACE_IS_KERNEL_P(vm)) { 245 return kcopy(kaddr, uaddr, len); 246 } 247 if (__predict_true(vm == curproc->p_vmspace)) { 248 return copyout(kaddr, uaddr, len); 249 } 250 251 iov.iov_base = __UNCONST(kaddr); /* XXXUNCONST cast away const */ 252 iov.iov_len = len; 253 uio.uio_iov = &iov; 254 uio.uio_iovcnt = 1; 255 uio.uio_offset = (off_t)(uintptr_t)uaddr; 256 uio.uio_resid = len; 257 uio.uio_rw = UIO_WRITE; 258 UIO_SETUP_SYSSPACE(&uio); 259 error = uvm_io(&vm->vm_map, &uio, 0); 260 261 return (error); 262 } 263 264 /* 265 * Like copyin(), but operates on an arbitrary process. 266 */ 267 int 268 copyin_proc(struct proc *p, const void *uaddr, void *kaddr, size_t len) 269 { 270 struct vmspace *vm; 271 int error; 272 273 error = proc_vmspace_getref(p, &vm); 274 if (error) { 275 return error; 276 } 277 error = copyin_vmspace(vm, uaddr, kaddr, len); 278 uvmspace_free(vm); 279 280 return error; 281 } 282 283 /* 284 * Like copyout(), but operates on an arbitrary process. 285 */ 286 int 287 copyout_proc(struct proc *p, const void *kaddr, void *uaddr, size_t len) 288 { 289 struct vmspace *vm; 290 int error; 291 292 error = proc_vmspace_getref(p, &vm); 293 if (error) { 294 return error; 295 } 296 error = copyout_vmspace(vm, kaddr, uaddr, len); 297 uvmspace_free(vm); 298 299 return error; 300 } 301 302 /* 303 * Like copyin(), but operates on an arbitrary pid. 304 */ 305 int 306 copyin_pid(pid_t pid, const void *uaddr, void *kaddr, size_t len) 307 { 308 struct proc *p; 309 struct vmspace *vm; 310 int error; 311 312 mutex_enter(proc_lock); 313 p = proc_find(pid); 314 if (p == NULL) { 315 mutex_exit(proc_lock); 316 return ESRCH; 317 } 318 mutex_enter(p->p_lock); 319 proc_vmspace_getref(p, &vm); 320 mutex_exit(p->p_lock); 321 mutex_exit(proc_lock); 322 323 error = copyin_vmspace(vm, uaddr, kaddr, len); 324 325 uvmspace_free(vm); 326 return error; 327 } 328 329 /* 330 * Like copyin(), except it operates on kernel addresses when the FKIOCTL 331 * flag is passed in `ioctlflags' from the ioctl call. 332 */ 333 int 334 ioctl_copyin(int ioctlflags, const void *src, void *dst, size_t len) 335 { 336 if (ioctlflags & FKIOCTL) 337 return kcopy(src, dst, len); 338 return copyin(src, dst, len); 339 } 340 341 /* 342 * Like copyout(), except it operates on kernel addresses when the FKIOCTL 343 * flag is passed in `ioctlflags' from the ioctl call. 344 */ 345 int 346 ioctl_copyout(int ioctlflags, const void *src, void *dst, size_t len) 347 { 348 if (ioctlflags & FKIOCTL) 349 return kcopy(src, dst, len); 350 return copyout(src, dst, len); 351 } 352