| 1 | /* $NetBSD: subr_copy.c,v 1.7 2016/05/25 17:43:58 christos 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 1.7 2016/05/25 17:43:58 christos 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(), except it operates on kernel addresses when the FKIOCTL |
| 304 | * flag is passed in `ioctlflags' from the ioctl call. |
| 305 | */ |
| 306 | int |
| 307 | ioctl_copyin(int ioctlflags, const void *src, void *dst, size_t len) |
| 308 | { |
| 309 | if (ioctlflags & FKIOCTL) |
| 310 | return kcopy(src, dst, len); |
| 311 | return copyin(src, dst, len); |
| 312 | } |
| 313 | |
| 314 | /* |
| 315 | * Like copyout(), except it operates on kernel addresses when the FKIOCTL |
| 316 | * flag is passed in `ioctlflags' from the ioctl call. |
| 317 | */ |
| 318 | int |
| 319 | ioctl_copyout(int ioctlflags, const void *src, void *dst, size_t len) |
| 320 | { |
| 321 | if (ioctlflags & FKIOCTL) |
| 322 | return kcopy(src, dst, len); |
| 323 | return copyout(src, dst, len); |
| 324 | } |
| 325 | |