1 /* $NetBSD: linux_ptrace.c,v 1.17 2007/12/20 23:02:53 dsl 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 1.17 2007/12/20 23:02:53 dsl 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 /* XXX Check me! (From NetBSD/i386) */ 107 int 108 linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, register_t *retval) 109 { 110 /* { 111 syscallarg(int) request; 112 syscallarg(int) pid; 113 syscallarg(int) addr; 114 syscallarg(int) data; 115 } */ 116 int request, error; 117 struct proc *p = l->l_proc; 118 struct proc *t; /* target process */ 119 struct lwp *lt; 120 struct reg *regs = NULL; 121 struct fpreg *fpregs = NULL; 122 struct linux_pt_regs *linux_regs = NULL; 123 double *linux_fpreg = NULL; /* it's an array, not a struct */ 124 int addr; 125 int i; 126 127 switch (request = SCARG(uap, request)) { 128 case LINUX_PTRACE_PEEKUSR: 129 case LINUX_PTRACE_POKEUSR: 130 case LINUX_PTRACE_GETREGS: 131 case LINUX_PTRACE_SETREGS: 132 case LINUX_PTRACE_GETFPREGS: 133 case LINUX_PTRACE_SETFPREGS: 134 break; 135 default: 136 return EIO; 137 } 138 139 /* Find the process we're supposed to be operating on. */ 140 if ((t = pfind(SCARG(uap, pid))) == NULL) 141 return ESRCH; 142 143 /* 144 * You can't do what you want to the process if: 145 * (1) It's not being traced at all, 146 */ 147 if (!ISSET(t->p_slflag, PSL_TRACED)) /* XXXSMP */ 148 return EPERM; 149 150 /* 151 * (2) it's being traced by procfs (which has 152 * different signal delivery semantics), 153 */ 154 if (ISSET(t->p_slflag, PSL_FSTRACE)) 155 return EBUSY; 156 157 /* 158 * (3) it's not being traced by _you_, or 159 */ 160 if (t->p_pptr != p) 161 return EBUSY; 162 163 /* 164 * (4) it's not currently stopped. 165 */ 166 if (t->p_stat != SSTOP || !t->p_waited) 167 return EBUSY; 168 169 lt = LIST_FIRST(&t->p_lwps); 170 *retval = 0; 171 172 switch (request) { 173 case LINUX_PTRACE_GETREGS: 174 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 175 MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs), 176 M_TEMP, M_WAITOK); 177 178 error = process_read_regs(lt, regs); 179 if (error != 0) 180 goto out; 181 182 for (i=0; i<=31; i++) 183 linux_regs->lgpr[i] = regs->fixreg[i]; 184 linux_regs->lnip = regs->pc; 185 linux_regs->lmsr = 0; 186 /* XXX Is that right? */ 187 linux_regs->lorig_gpr3 = regs->fixreg[3]; 188 linux_regs->lctr = regs->ctr; 189 linux_regs->llink = regs->lr; 190 linux_regs->lxer = regs->xer; 191 linux_regs->lccr = regs->cr; 192 linux_regs->lmq = 0; 193 linux_regs->ltrap = 0; 194 linux_regs->ldar = 0; 195 linux_regs->ldsisr = 0; 196 linux_regs->lresult = 0; 197 198 error = copyout(linux_regs, (void *)SCARG(uap, data), 199 sizeof(struct linux_pt_regs)); 200 goto out; 201 202 case LINUX_PTRACE_SETREGS: 203 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 204 MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs), 205 M_TEMP, M_WAITOK); 206 207 error = copyin((void *)SCARG(uap, data), linux_regs, 208 sizeof(struct linux_pt_regs)); 209 if (error != 0) 210 goto out; 211 212 for (i=0; i<=31; i++) 213 regs->fixreg[i] = linux_regs->lgpr[i]; 214 regs->lr = linux_regs->llink; 215 regs->cr = linux_regs->lccr; 216 regs->xer = linux_regs->lxer; 217 regs->ctr = linux_regs->lctr; 218 regs->pc = linux_regs->lnip; /* XXX */ 219 220 error = process_write_regs(lt, regs); 221 goto out; 222 223 case LINUX_PTRACE_GETFPREGS: 224 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 225 M_TEMP, M_WAITOK); 226 MALLOC(linux_fpreg, double *, 227 32*sizeof(double), M_TEMP, M_WAITOK); 228 229 error = process_read_fpregs(lt, fpregs); 230 if (error != 0) 231 goto out; 232 233 /* zero the contents if NetBSD fpreg structure is smaller */ 234 if (sizeof(struct fpreg) < (32*sizeof(double))) 235 memset(linux_fpreg, '\0', (32*sizeof(double))); 236 237 memcpy(linux_fpreg, fpregs, 238 min(32*sizeof(double), sizeof(struct fpreg))); 239 error = copyout(linux_fpreg, (void *)SCARG(uap, data), 240 32*sizeof(double)); 241 goto out; 242 243 case LINUX_PTRACE_SETFPREGS: 244 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 245 M_TEMP, M_WAITOK); 246 MALLOC(linux_fpreg, double *, 247 32*sizeof(double), M_TEMP, M_WAITOK); 248 error = copyin((void *)SCARG(uap, data), linux_fpreg, 249 32*sizeof(double)); 250 if (error != 0) 251 goto out; 252 253 memset(fpregs, '\0', sizeof(struct fpreg)); 254 memcpy(fpregs, linux_fpreg, 255 min(32*sizeof(double), sizeof(struct fpreg))); 256 257 error = process_write_fpregs(lt, fpregs); 258 goto out; 259 260 case LINUX_PTRACE_PEEKUSR: 261 addr = SCARG(uap, addr); 262 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 263 error = process_read_regs(lt, regs); 264 if (error) 265 goto out; 266 267 uvm_lwp_hold(lt); /* need full process info */ 268 error = 0; 269 if ((addr < LUSR_OFF(lusr_startgdb)) || 270 (addr > LUSR_OFF(lu_comm_end))) 271 error = 1; 272 else if (addr == LUSR_OFF(u_tsize)) 273 *retval = p->p_vmspace->vm_tsize; 274 else if (addr == LUSR_OFF(u_dsize)) 275 *retval = p->p_vmspace->vm_dsize; 276 else if (addr == LUSR_OFF(u_ssize)) 277 *retval = p->p_vmspace->vm_ssize; 278 else if (addr == LUSR_OFF(start_code)) 279 *retval = (register_t) p->p_vmspace->vm_taddr; 280 else if (addr == LUSR_OFF(start_stack)) 281 *retval = (register_t) p->p_vmspace->vm_minsaddr; 282 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 283 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 284 *retval = regs->fixreg[addr / sizeof (register_t)]; 285 else if (addr == LUSR_REG_OFF(lnip)) 286 *retval = regs->pc; 287 else if (addr == LUSR_REG_OFF(lctr)) 288 *retval = regs->ctr; 289 else if (addr == LUSR_REG_OFF(llink)) 290 *retval = regs->lr; 291 else if (addr == LUSR_REG_OFF(lxer)) 292 *retval = regs->xer; 293 else if (addr == LUSR_REG_OFF(lccr)) 294 *retval = regs->cr; 295 else if (addr == LUSR_OFF(signal)) 296 error = 1; 297 else if (addr == LUSR_OFF(signal)) 298 error = 1; 299 else if (addr == LUSR_OFF(magic)) 300 error = 1; 301 else if (addr == LUSR_OFF(u_comm)) 302 error = 1; 303 else { 304 #ifdef DEBUG_LINUX 305 printf("linux_ptrace: unsupported address: %d\n", addr); 306 #endif 307 error = 1; 308 } 309 310 uvm_lwp_rele(lt); 311 312 if (error) 313 goto out; 314 315 error = copyout (retval, 316 (void *)SCARG(uap, data), sizeof retval); 317 *retval = SCARG(uap, data); 318 319 goto out; 320 321 break; 322 323 case LINUX_PTRACE_POKEUSR: /* XXX Not tested */ 324 addr = SCARG(uap, addr); 325 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 326 error = process_read_regs(lt, regs); 327 if (error) 328 goto out; 329 330 uvm_lwp_hold(lt); /* need full process info */ 331 error = 0; 332 if ((addr < LUSR_OFF(lusr_startgdb)) || 333 (addr > LUSR_OFF(lu_comm_end))) 334 error = 1; 335 else if (addr == LUSR_OFF(u_tsize)) 336 error = 1; 337 else if (addr == LUSR_OFF(u_dsize)) 338 error = 1; 339 else if (addr == LUSR_OFF(u_ssize)) 340 error = 1; 341 else if (addr == LUSR_OFF(start_code)) 342 error = 1; 343 else if (addr == LUSR_OFF(start_stack)) 344 error = 1; 345 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 346 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 347 regs->fixreg[addr / sizeof (register_t)] = 348 (register_t)SCARG(uap, data); 349 else if (addr == LUSR_REG_OFF(lnip)) 350 regs->pc = (register_t)SCARG(uap, data); 351 else if (addr == LUSR_REG_OFF(lctr)) 352 regs->ctr = (register_t)SCARG(uap, data); 353 else if (addr == LUSR_REG_OFF(llink)) 354 regs->lr = (register_t)SCARG(uap, data); 355 else if (addr == LUSR_REG_OFF(lxer)) 356 regs->xer = (register_t)SCARG(uap, data); 357 else if (addr == LUSR_REG_OFF(lccr)) 358 regs->cr = (register_t)SCARG(uap, data); 359 else if (addr == LUSR_OFF(signal)) 360 error = 1; 361 else if (addr == LUSR_OFF(magic)) 362 error = 1; 363 else if (addr == LUSR_OFF(u_comm)) 364 error = 1; 365 else { 366 #ifdef DEBUG_LINUX 367 printf("linux_ptrace: unsupported address: %d\n", addr); 368 #endif 369 error = 1; 370 } 371 372 uvm_lwp_rele(lt); 373 374 error = process_write_regs(lt,regs); 375 if (error) 376 goto out; 377 378 break; 379 default: 380 /* never reached */ 381 break; 382 } 383 return EIO; 384 385 out: 386 if (regs) 387 FREE(regs, M_TEMP); 388 if (fpregs) 389 FREE(fpregs, M_TEMP); 390 if (linux_regs) 391 FREE(linux_regs, M_TEMP); 392 if (linux_fpreg) 393 FREE(linux_fpreg, M_TEMP); 394 return (error); 395 } 396