linux_ptrace.c revision 1.5
1 /* $NetBSD: linux_ptrace.c,v 1.5 2000/11/21 12:28:15 jdolecek Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 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. 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/types.h> 40 #include <sys/param.h> 41 #include <sys/malloc.h> 42 #include <sys/mount.h> 43 #include <sys/proc.h> 44 #include <sys/ptrace.h> 45 #include <sys/systm.h> 46 #include <sys/syscallargs.h> 47 #include <uvm/uvm_extern.h> 48 49 #include <machine/reg.h> 50 51 #include <compat/linux/common/linux_types.h> 52 #include <compat/linux/common/linux_ptrace.h> 53 #include <compat/linux/common/linux_signal.h> 54 55 #include <compat/linux/common/linux_util.h> 56 #include <compat/linux/common/linux_machdep.h> 57 #include <compat/linux/common/linux_emuldata.h> 58 #include <compat/linux/common/linux_exec.h> /* for emul_linux */ 59 60 #include <compat/linux/linux_syscallargs.h> 61 62 #include <lib/libkern/libkern.h> /* for offsetof() */ 63 64 struct linux_reg { 65 long ebx; 66 long ecx; 67 long edx; 68 long esi; 69 long edi; 70 long ebp; 71 long eax; 72 long xds, xes; // unsigned short ds, __ds, es, __es; 73 long __fs, __gs; // unsigned short fs, __fs, gs, __gs; 74 long orig_eax; 75 long eip; 76 long xcs; // unsigned short cs, __cs; 77 long eflags; 78 long esp; 79 long xss; // unsigned short ss, __ss 80 }; 81 82 /* structure used for storing floating point context */ 83 struct linux_fpreg { 84 long cwd; 85 long swd; 86 long twd; 87 long fip; 88 long fcs; 89 long foo; 90 long fos; 91 long st_space [20]; 92 }; 93 94 /* user struct for linux process - this is used for Linux ptrace emulation */ 95 /* most of it is junk only used by gdb */ 96 struct linux_user { 97 struct linux_reg regs; /* registers */ 98 int u_fpvalid; /* true if math co-processor being used. */ 99 struct linux_fpreg i387; /* Math Co-processor registers. */ 100 /* The rest of this junk is to help gdb figure out what goes where */ 101 #define lusr_startgdb u_tsize 102 unsigned long int u_tsize; /* Text segment size (pages). */ 103 unsigned long int u_dsize; /* Data segment size (pages). */ 104 unsigned long int u_ssize; /* Stack segment size (pages). */ 105 unsigned long start_code; /* Starting virtual address of text. */ 106 unsigned long start_stack; /* Starting virtual address of stack area. 107 This is actually the bottom of the stack, 108 the top of the stack is always found in the 109 esp register. */ 110 long int __signal; /* Signal that caused the core dump. */ 111 int __reserved; /* unused */ 112 void * u_ar0; /* Used by gdb to help find the values for */ 113 /* the registers. */ 114 struct linux_fpreg* u_fpstate;/* Math Co-processor pointer. */ 115 unsigned long __magic; /* To uniquely identify a core file */ 116 char u_comm[32]; /* User command that was responsible */ 117 int u_debugreg[8]; 118 #define u_debugreg_end u_debugreg[7] 119 }; 120 121 #define LUSR_OFF(member) offsetof(struct linux_user, member) 122 #define ISSET(t, f) ((t) & (f)) 123 124 int 125 linux_sys_ptrace_arch(p, v, retval) 126 struct proc *p; 127 void *v; 128 register_t *retval; 129 { 130 struct linux_sys_ptrace_args /* { 131 syscallarg(int) request; 132 syscallarg(int) pid; 133 syscallarg(int) addr; 134 syscallarg(int) data; 135 } */ *uap = v; 136 int request, error; 137 struct proc *t; /* target process */ 138 struct reg *regs = NULL; 139 struct fpreg *fpregs = NULL; 140 struct linux_reg *linux_regs = NULL; 141 struct linux_fpreg *linux_fpregs = NULL; 142 int addr; 143 144 request = SCARG(uap, request); 145 146 if ((request != LINUX_PTRACE_PEEKUSR) && 147 (request != LINUX_PTRACE_POKEUSR) && 148 (request != LINUX_PTRACE_GETREGS) && 149 (request != LINUX_PTRACE_SETREGS) && 150 (request != LINUX_PTRACE_GETFPREGS) && 151 (request != LINUX_PTRACE_SETFPREGS)) 152 return EIO; 153 154 /* Find the process we're supposed to be operating on. */ 155 if ((t = pfind(SCARG(uap, pid))) == NULL) 156 return ESRCH; 157 158 /* 159 * You can't do what you want to the process if: 160 * (1) It's not being traced at all, 161 */ 162 if (!ISSET(t->p_flag, P_TRACED)) 163 return EPERM; 164 165 /* 166 * (2) it's being traced by procfs (which has 167 * different signal delivery semantics), 168 */ 169 if (ISSET(t->p_flag, P_FSTRACE)) 170 return EBUSY; 171 172 /* 173 * (3) it's not being traced by _you_, or 174 */ 175 if (t->p_pptr != p) 176 return EBUSY; 177 178 /* 179 * (4) it's not currently stopped. 180 */ 181 if (t->p_stat != SSTOP || !ISSET(t->p_flag, P_WAITED)) 182 return EBUSY; 183 184 *retval = 0; 185 186 switch (request) { 187 case LINUX_PTRACE_GETREGS: 188 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 189 MALLOC(linux_regs, struct linux_reg*, sizeof(struct linux_reg), 190 M_TEMP, M_WAITOK); 191 192 error = process_read_regs(t, regs); 193 if (error != 0) 194 goto out; 195 196 linux_regs->ebx = regs->r_ebx; 197 linux_regs->ecx = regs->r_ecx; 198 linux_regs->edx = regs->r_edx; 199 linux_regs->esi = regs->r_esi; 200 linux_regs->edi = regs->r_edi; 201 linux_regs->ebp = regs->r_ebp; 202 linux_regs->eax = regs->r_eax; 203 linux_regs->xds = regs->r_ds; 204 linux_regs->xes = regs->r_es; 205 linux_regs->orig_eax = regs->r_eax; /* XXX is this correct? */ 206 linux_regs->eip = regs->r_cs + regs->r_eip; 207 linux_regs->xcs = regs->r_cs; 208 linux_regs->eflags = regs->r_eflags; 209 linux_regs->esp = regs->r_esp; 210 linux_regs->xss = regs->r_ss; 211 212 error = copyout(linux_regs, (caddr_t)SCARG(uap, data), 213 sizeof(struct linux_reg)); 214 goto out; 215 216 case LINUX_PTRACE_SETREGS: 217 MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK); 218 MALLOC(linux_regs, struct linux_reg *, sizeof(struct linux_reg), 219 M_TEMP, M_WAITOK); 220 221 error = copyin((caddr_t)SCARG(uap, data), linux_regs, 222 sizeof(struct linux_reg)); 223 if (error != 0) 224 goto out; 225 226 regs->r_ebx = linux_regs->ebx; 227 regs->r_ecx = linux_regs->ecx; 228 regs->r_edx = linux_regs->edx; 229 regs->r_esi = linux_regs->esi; 230 regs->r_edi = linux_regs->edi; 231 regs->r_ebp = linux_regs->ebp; 232 regs->r_eax = linux_regs->eax; 233 regs->r_ds = linux_regs->xds; 234 regs->r_es = linux_regs->xes; 235 regs->r_eip = linux_regs->eip - linux_regs->xcs; 236 regs->r_cs = linux_regs->xcs; 237 regs->r_eflags = linux_regs->eflags; 238 regs->r_esp = linux_regs->esp; 239 regs->r_ss = linux_regs->xss; 240 241 error = process_write_regs(t, regs); 242 goto out; 243 244 case LINUX_PTRACE_GETFPREGS: 245 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 246 M_TEMP, M_WAITOK); 247 MALLOC(linux_fpregs, struct linux_fpreg *, 248 sizeof(struct linux_fpreg), M_TEMP, M_WAITOK); 249 250 error = process_read_fpregs(t, fpregs); 251 if (error != 0) 252 goto out; 253 254 /* zero the contents if NetBSD fpreg structure is smaller */ 255 if (sizeof(struct fpreg) < sizeof(struct linux_fpreg)) 256 memset(linux_fpregs, '\0', sizeof(struct linux_fpreg)); 257 258 memcpy(linux_fpregs, fpregs, 259 min(sizeof(struct linux_fpreg), sizeof(struct fpreg))); 260 error = copyout(linux_fpregs, (caddr_t)SCARG(uap, data), 261 sizeof(struct linux_fpreg)); 262 goto out; 263 264 case LINUX_PTRACE_SETFPREGS: 265 MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg), 266 M_TEMP, M_WAITOK); 267 MALLOC(linux_fpregs, struct linux_fpreg *, 268 sizeof(struct linux_fpreg), M_TEMP, M_WAITOK); 269 error = copyin((caddr_t)SCARG(uap, data), linux_fpregs, 270 sizeof(struct linux_fpreg)); 271 if (error != 0) 272 goto out; 273 274 memset(fpregs, '\0', sizeof(struct fpreg)); 275 memcpy(fpregs, linux_fpregs, 276 min(sizeof(struct linux_fpreg), sizeof(struct fpreg))); 277 278 error = process_write_regs(t, regs); 279 goto out; 280 281 case LINUX_PTRACE_PEEKUSR: 282 addr = SCARG(uap, addr); 283 284 PHOLD(t); /* need full process info */ 285 error = 0; 286 if (addr < LUSR_OFF(lusr_startgdb)) { 287 /* XXX should provide appropriate register */ 288 error = 1; 289 } else if (addr == LUSR_OFF(u_tsize)) 290 *retval = p->p_vmspace->vm_tsize; 291 else if (addr == LUSR_OFF(u_dsize)) 292 *retval = p->p_vmspace->vm_dsize; 293 else if (addr == LUSR_OFF(u_ssize)) 294 *retval = p->p_vmspace->vm_ssize; 295 else if (addr == LUSR_OFF(start_code)) 296 *retval = (register_t) p->p_vmspace->vm_taddr; 297 else if (addr == LUSR_OFF(start_stack)) 298 *retval = (register_t) p->p_vmspace->vm_minsaddr; 299 else if (addr == LUSR_OFF(u_ar0)) 300 *retval = LUSR_OFF(regs); 301 else if (addr >= LUSR_OFF(u_debugreg) 302 && addr <= LUSR_OFF(u_debugreg_end)) { 303 int off = (addr - LUSR_OFF(u_debugreg)) / sizeof(int); 304 305 /* only do this for Linux processes */ 306 if (t->p_emul != &emul_linux) 307 error = EINVAL; 308 else { 309 *retval = ((struct linux_emuldata *) 310 t->p_emuldata)->debugreg[off]; 311 } 312 } else if (addr == LUSR_OFF(__signal)) { 313 error = 1; 314 } else if (addr == LUSR_OFF(__signal)) { 315 error = 1; 316 } else if (addr == LUSR_OFF(u_fpstate)) { 317 error = 1; 318 } else if (addr == LUSR_OFF(__magic)) { 319 error = 1; 320 } else if (addr == LUSR_OFF(u_comm)) { 321 error = 1; 322 } else { 323 #ifdef DEBUG_LINUX 324 printf("linux_ptrace: unsupported address: %d\n", addr); 325 #endif 326 error = 1; 327 } 328 329 PRELE(t); 330 331 if (!error) 332 return 0; 333 334 case LINUX_PTRACE_POKEUSR: 335 /* we only support setting debugregs for now */ 336 addr = SCARG(uap, addr); 337 if (addr >= LUSR_OFF(u_debugreg) 338 && addr <= LUSR_OFF(u_debugreg_end)) { 339 int off = (addr - LUSR_OFF(u_debugreg)) / sizeof(int); 340 int data = SCARG(uap, data); 341 342 /* only do this for Linux processes */ 343 if (t->p_emul != &emul_linux) 344 return EINVAL; 345 346 PHOLD(t); 347 ((struct linux_emuldata *)t->p_emuldata)->debugreg[off] = data; 348 PRELE(t); 349 return (0); 350 } 351 352 break; 353 default: 354 /* never reached */ 355 break; 356 } 357 358 return EIO; 359 360 out: 361 if (regs) 362 FREE(regs, M_TEMP); 363 if (fpregs) 364 FREE(fpregs, M_TEMP); 365 if (linux_regs) 366 FREE(linux_regs, M_TEMP); 367 if (linux_fpregs) 368 FREE(linux_fpregs, M_TEMP); 369 return (error); 370 } 371
Indexes created Mon Sep 22 21:09:42 GMT 2025