1 /* $NetBSD: linux_ptrace.c,v 1.18 2008/04/23 14:18:50 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matthias Scheler and Emmanuel Dreyfus. 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.18 2008/04/23 14:18:50 ad Exp $"); 41 42 #include "opt_ptrace.h" 43 44 #include <sys/param.h> 45 #include <sys/malloc.h> 46 #include <sys/mount.h> 47 #include <sys/proc.h> 48 #include <sys/ptrace.h> 49 #include <sys/systm.h> 50 #include <sys/syscallargs.h> 51 #include <uvm/uvm_extern.h> 52 53 #include <machine/reg.h> 54 55 #include <compat/linux/common/linux_types.h> 56 #include <compat/linux/common/linux_ptrace.h> 57 #include <compat/linux/common/linux_signal.h> 58 59 #include <compat/linux/common/linux_util.h> 60 #include <compat/linux/common/linux_machdep.h> 61 #include <compat/linux/common/linux_emuldata.h> 62 #include <compat/linux/common/linux_exec.h> /* for emul_linux */ 63 64 #include <compat/linux/linux_syscallargs.h> 65 66 #include <lib/libkern/libkern.h> /* for offsetof() */ 67 68 /* 69 * From Linux's include/asm-ppc/ptrace.h. 70 * structure used for storing reg context: defined in linux_machdep.h 71 * structure used for storing floating point context: 72 * Linux just uses a double fpr[32], no struct 73 */ 74 75 /* 76 * user struct for linux process - this is used for Linux ptrace emulation 77 * most of it is junk only used by gdb 78 * 79 * From Linux's include/asm-ppc/user.h 80 * 81 * XXX u_ar0 was a struct reg in Linux/powerpc 82 * Can't find out what a struct regs is for Linux/powerpc, 83 * so we use a struct pt_regs instead. don't know if this is right. 84 */ 85 86 struct linux_user { 87 struct linux_pt_regs regs; 88 #define lusr_startgdb regs 89 size_t u_tsize; 90 size_t u_dsize; 91 size_t u_ssize; 92 unsigned long start_code; 93 unsigned long start_data; 94 unsigned long start_stack; 95 long int signal; 96 struct linux_pt_regs *u_ar0; /* help gdb find registers */ 97 unsigned long magic; 98 char u_comm[32]; 99 #define lu_comm_end u_comm[31] 100 }; 101 102 #define LUSR_OFF(member) offsetof(struct linux_user, member) 103 #define LUSR_REG_OFF(member) offsetof(struct linux_pt_regs, member) 104 #define ISSET(t, f) ((t) & (f)) 105 106 int linux_ptrace_disabled = 1; /* bitrotted */ 107 108 /* XXX Check me! (From NetBSD/i386) */ 109 int 110 linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, register_t *retval) 111 { 112 /* { 113 syscallarg(int) request; 114 syscallarg(int) pid; 115 syscallarg(int) addr; 116 syscallarg(int) data; 117 } */ 118 int request, error; 119 struct proc *p = l->l_proc; 120 struct proc *t; /* target process */ 121 struct lwp *lt; 122 struct reg *regs = NULL; 123 struct fpreg *fpregs = NULL; 124 struct linux_pt_regs *linux_regs = NULL; 125 double *linux_fpreg = NULL; /* it's an array, not a struct */ 126 int addr; 127 int i; 128 129 if (linux_ptrace_disabled) 130 return ENOSYS; 131 132 switch (request = SCARG(uap, request)) { 133 case LINUX_PTRACE_PEEKUSR: 134 case LINUX_PTRACE_POKEUSR: 135 case LINUX_PTRACE_GETREGS: 136 case LINUX_PTRACE_SETREGS: 137 case LINUX_PTRACE_GETFPREGS: 138 case LINUX_PTRACE_SETFPREGS: 139 break; 140 default: 141 return EIO; 142 } 143 144 /* Find the process we're supposed to be operating on. */ 145 if ((t = pfind(SCARG(uap, pid))) == NULL) 146 return ESRCH; 147 148 /* 149 * You can't do what you want to the process if: 150 * (1) It's not being traced at all, 151 */ 152 if (!ISSET(t->p_slflag, PSL_TRACED)) /* XXXSMP */ 153 return EPERM; 154 155 /* 156 * (2) it's being traced by procfs (which has 157 * different signal delivery semantics), 158 */ 159 if (ISSET(t->p_slflag, PSL_FSTRACE)) 160 return EBUSY; 161 162 /* 163 * (3) it's not being traced by _you_, or 164 */ 165 if (t->p_pptr != p) 166 return EBUSY; 167 168 /* 169 * (4) it's not currently stopped. 170 */ 171 if (t->p_stat != SSTOP || !t->p_waited) 172 return EBUSY; 173 174 lt = LIST_FIRST(&t->p_lwps); 175 *retval = 0; 176 177 switch (request) { 178 case LINUX_PTRACE_GETREGS: 179 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 180 MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs), 181 M_TEMP, M_WAITOK); 182 183 error = process_read_regs(lt, regs); 184 if (error != 0) 185 goto out; 186 187 for (i=0; i<=31; i++) 188 linux_regs->lgpr[i] = regs->fixreg[i]; 189 linux_regs->lnip = regs->pc; 190 linux_regs->lmsr = 0; 191 /* XXX Is that right? */ 192 linux_regs->lorig_gpr3 = regs->fixreg[3]; 193 linux_regs->lctr = regs->ctr; 194 linux_regs->llink = regs->lr; 195 linux_regs->lxer = regs->xer; 196 linux_regs->lccr = regs->cr; 197 linux_regs->lmq = 0; 198 linux_regs->ltrap = 0; 199 linux_regs->ldar = 0; 200 linux_regs->ldsisr = 0; 201 linux_regs->lresult = 0; 202 203 error = copyout(linux_regs, (void *)SCARG(uap, data), 204 sizeof(struct linux_pt_regs)); 205 goto out; 206 207 case LINUX_PTRACE_SETREGS: 208 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 209 MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs), 210 M_TEMP, M_WAITOK); 211 212 error = copyin((void *)SCARG(uap, data), linux_regs, 213 sizeof(struct linux_pt_regs)); 214 if (error != 0) 215 goto out; 216 217 for (i=0; i<=31; i++) 218 regs->fixreg[i] = linux_regs->lgpr[i]; 219 regs->lr = linux_regs->llink; 220 regs->cr = linux_regs->lccr; 221 regs->xer = linux_regs->lxer; 222 regs->ctr = linux_regs->lctr; 223 regs->pc = linux_regs->lnip; /* XXX */ 224 225 error = process_write_regs(lt, regs); 226 goto out; 227 228 case LINUX_PTRACE_GETFPREGS: 229 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 230 M_TEMP, M_WAITOK); 231 MALLOC(linux_fpreg, double *, 232 32*sizeof(double), M_TEMP, M_WAITOK); 233 234 error = process_read_fpregs(lt, fpregs); 235 if (error != 0) 236 goto out; 237 238 /* zero the contents if NetBSD fpreg structure is smaller */ 239 if (sizeof(struct fpreg) < (32*sizeof(double))) 240 memset(linux_fpreg, '\0', (32*sizeof(double))); 241 242 memcpy(linux_fpreg, fpregs, 243 min(32*sizeof(double), sizeof(struct fpreg))); 244 error = copyout(linux_fpreg, (void *)SCARG(uap, data), 245 32*sizeof(double)); 246 goto out; 247 248 case LINUX_PTRACE_SETFPREGS: 249 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 250 M_TEMP, M_WAITOK); 251 MALLOC(linux_fpreg, double *, 252 32*sizeof(double), M_TEMP, M_WAITOK); 253 error = copyin((void *)SCARG(uap, data), linux_fpreg, 254 32*sizeof(double)); 255 if (error != 0) 256 goto out; 257 258 memset(fpregs, '\0', sizeof(struct fpreg)); 259 memcpy(fpregs, linux_fpreg, 260 min(32*sizeof(double), sizeof(struct fpreg))); 261 262 error = process_write_fpregs(lt, fpregs); 263 goto out; 264 265 case LINUX_PTRACE_PEEKUSR: 266 addr = SCARG(uap, addr); 267 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 268 error = process_read_regs(lt, regs); 269 if (error) 270 goto out; 271 272 uvm_lwp_hold(lt); /* need full process info */ 273 error = 0; 274 if ((addr < LUSR_OFF(lusr_startgdb)) || 275 (addr > LUSR_OFF(lu_comm_end))) 276 error = 1; 277 else if (addr == LUSR_OFF(u_tsize)) 278 *retval = p->p_vmspace->vm_tsize; 279 else if (addr == LUSR_OFF(u_dsize)) 280 *retval = p->p_vmspace->vm_dsize; 281 else if (addr == LUSR_OFF(u_ssize)) 282 *retval = p->p_vmspace->vm_ssize; 283 else if (addr == LUSR_OFF(start_code)) 284 *retval = (register_t) p->p_vmspace->vm_taddr; 285 else if (addr == LUSR_OFF(start_stack)) 286 *retval = (register_t) p->p_vmspace->vm_minsaddr; 287 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 288 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 289 *retval = regs->fixreg[addr / sizeof (register_t)]; 290 else if (addr == LUSR_REG_OFF(lnip)) 291 *retval = regs->pc; 292 else if (addr == LUSR_REG_OFF(lctr)) 293 *retval = regs->ctr; 294 else if (addr == LUSR_REG_OFF(llink)) 295 *retval = regs->lr; 296 else if (addr == LUSR_REG_OFF(lxer)) 297 *retval = regs->xer; 298 else if (addr == LUSR_REG_OFF(lccr)) 299 *retval = regs->cr; 300 else if (addr == LUSR_OFF(signal)) 301 error = 1; 302 else if (addr == LUSR_OFF(signal)) 303 error = 1; 304 else if (addr == LUSR_OFF(magic)) 305 error = 1; 306 else if (addr == LUSR_OFF(u_comm)) 307 error = 1; 308 else { 309 #ifdef DEBUG_LINUX 310 printf("linux_ptrace: unsupported address: %d\n", addr); 311 #endif 312 error = 1; 313 } 314 315 uvm_lwp_rele(lt); 316 317 if (error) 318 goto out; 319 320 error = copyout (retval, 321 (void *)SCARG(uap, data), sizeof retval); 322 *retval = SCARG(uap, data); 323 324 goto out; 325 326 break; 327 328 case LINUX_PTRACE_POKEUSR: /* XXX Not tested */ 329 addr = SCARG(uap, addr); 330 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 331 error = process_read_regs(lt, regs); 332 if (error) 333 goto out; 334 335 uvm_lwp_hold(lt); /* need full process info */ 336 error = 0; 337 if ((addr < LUSR_OFF(lusr_startgdb)) || 338 (addr > LUSR_OFF(lu_comm_end))) 339 error = 1; 340 else if (addr == LUSR_OFF(u_tsize)) 341 error = 1; 342 else if (addr == LUSR_OFF(u_dsize)) 343 error = 1; 344 else if (addr == LUSR_OFF(u_ssize)) 345 error = 1; 346 else if (addr == LUSR_OFF(start_code)) 347 error = 1; 348 else if (addr == LUSR_OFF(start_stack)) 349 error = 1; 350 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 351 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 352 regs->fixreg[addr / sizeof (register_t)] = 353 (register_t)SCARG(uap, data); 354 else if (addr == LUSR_REG_OFF(lnip)) 355 regs->pc = (register_t)SCARG(uap, data); 356 else if (addr == LUSR_REG_OFF(lctr)) 357 regs->ctr = (register_t)SCARG(uap, data); 358 else if (addr == LUSR_REG_OFF(llink)) 359 regs->lr = (register_t)SCARG(uap, data); 360 else if (addr == LUSR_REG_OFF(lxer)) 361 regs->xer = (register_t)SCARG(uap, data); 362 else if (addr == LUSR_REG_OFF(lccr)) 363 regs->cr = (register_t)SCARG(uap, data); 364 else if (addr == LUSR_OFF(signal)) 365 error = 1; 366 else if (addr == LUSR_OFF(magic)) 367 error = 1; 368 else if (addr == LUSR_OFF(u_comm)) 369 error = 1; 370 else { 371 #ifdef DEBUG_LINUX 372 printf("linux_ptrace: unsupported address: %d\n", addr); 373 #endif 374 error = 1; 375 } 376 377 uvm_lwp_rele(lt); 378 379 error = process_write_regs(lt,regs); 380 if (error) 381 goto out; 382 383 break; 384 default: 385 /* never reached */ 386 break; 387 } 388 return EIO; 389 390 out: 391 if (regs) 392 FREE(regs, M_TEMP); 393 if (fpregs) 394 FREE(fpregs, M_TEMP); 395 if (linux_regs) 396 FREE(linux_regs, M_TEMP); 397 if (linux_fpreg) 398 FREE(linux_fpreg, M_TEMP); 399 return (error); 400 } 401