linux_ptrace.c revision 1.30
1 /* $NetBSD: linux_ptrace.c,v 1.30 2017/08/28 00:46:07 kamil 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.30 2017/08/28 00:46:07 kamil Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/mount.h> 37 #include <sys/proc.h> 38 #include <sys/ptrace.h> 39 #include <sys/systm.h> 40 #include <sys/syscallargs.h> 41 #include <uvm/uvm_extern.h> 42 43 #include <machine/reg.h> 44 45 #include <compat/linux/common/linux_types.h> 46 #include <compat/linux/common/linux_ptrace.h> 47 #include <compat/linux/common/linux_signal.h> 48 49 #include <compat/linux/common/linux_util.h> 50 #include <compat/linux/common/linux_machdep.h> 51 #include <compat/linux/common/linux_emuldata.h> 52 #include <compat/linux/common/linux_exec.h> /* for emul_linux */ 53 54 #include <compat/linux/linux_syscallargs.h> 55 56 #include <lib/libkern/libkern.h> /* for offsetof() */ 57 58 /* 59 * From Linux's include/asm-ppc/ptrace.h. 60 * structure used for storing reg context: defined in linux_machdep.h 61 * structure used for storing floating point context: 62 * Linux just uses a double fpr[32], no struct 63 */ 64 65 /* 66 * user struct for linux process - this is used for Linux ptrace emulation 67 * most of it is junk only used by gdb 68 * 69 * From Linux's include/asm-ppc/user.h 70 * 71 * XXX u_ar0 was a struct reg in Linux/powerpc 72 * Can't find out what a struct regs is for Linux/powerpc, 73 * so we use a struct pt_regs instead. don't know if this is right. 74 */ 75 76 struct linux_user { 77 struct linux_pt_regs regs; 78 #define lusr_startgdb regs 79 size_t u_tsize; 80 size_t u_dsize; 81 size_t u_ssize; 82 unsigned long start_code; 83 unsigned long start_data; 84 unsigned long start_stack; 85 long int signal; 86 struct linux_pt_regs *u_ar0; /* help gdb find registers */ 87 unsigned long magic; 88 char u_comm[32]; 89 #define lu_comm_end u_comm[31] 90 }; 91 92 #define LUSR_OFF(member) offsetof(struct linux_user, member) 93 #define LUSR_REG_OFF(member) offsetof(struct linux_pt_regs, member) 94 #define ISSET(t, f) ((t) & (f)) 95 96 int linux_ptrace_disabled = 1; /* bitrotted */ 97 98 /* XXX Check me! (From NetBSD/i386) */ 99 int 100 linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, 101 register_t *retval) 102 { 103 /* { 104 syscallarg(int) request; 105 syscallarg(int) pid; 106 syscallarg(int) addr; 107 syscallarg(int) data; 108 } */ 109 struct proc *p = l->l_proc, *t; 110 struct lwp *lt; 111 struct reg *regs = NULL; 112 struct fpreg *fpregs = NULL; 113 struct linux_pt_regs *linux_regs = NULL; 114 double *linux_fpreg = NULL; /* it's an array, not a struct */ 115 int request, error, addr, i; 116 117 if (linux_ptrace_disabled) 118 return ENOSYS; 119 120 error = 0; 121 request = SCARG(uap, request); 122 123 switch (request) { 124 case LINUX_PTRACE_PEEKUSR: 125 case LINUX_PTRACE_POKEUSR: 126 regs = kmem_alloc(sizeof(struct reg), KM_SLEEP); 127 break; 128 case LINUX_PTRACE_GETREGS: 129 case LINUX_PTRACE_SETREGS: 130 regs = kmem_alloc(sizeof(struct reg), KM_SLEEP); 131 linux_regs = kmem_alloc(sizeof(*linux_regs), KM_SLEEP); 132 if (request == LINUX_PTRACE_SETREGS) { 133 error = copyin((void *)SCARG(uap, data), linux_regs, 134 sizeof(struct linux_pt_regs)); 135 if (error) { 136 goto out; 137 } 138 } 139 break; 140 case LINUX_PTRACE_GETFPREGS: 141 case LINUX_PTRACE_SETFPREGS: 142 fpregs = kmem_alloc(sizeof(struct fpreg), KM_SLEEP); 143 linux_fpreg = kmem_alloc(32 * sizeof(double), KM_SLEEP); 144 if (request == LINUX_PTRACE_SETFPREGS) { 145 error = copyin((void *)SCARG(uap, data), linux_fpreg, 146 32 * sizeof(double)); 147 if (error) { 148 goto out; 149 } 150 } 151 break; 152 default: 153 error = EIO; 154 goto out; 155 } 156 157 /* Find the process we are supposed to be operating on. */ 158 mutex_enter(proc_lock); 159 if ((t = proc_find(SCARG(uap, pid))) == NULL) { 160 mutex_exit(proc_lock); 161 error = ESRCH; 162 goto out; 163 } 164 mutex_enter(t->p_lock); 165 166 /* 167 * You cannot do what you want to the process if: 168 * 1. It is not being traced at all, 169 */ 170 if (!ISSET(t->p_slflag, PSL_TRACED)) { 171 mutex_exit(t->p_lock); 172 mutex_exit(proc_lock); 173 error = EPERM; 174 goto out; 175 } 176 /* 177 * 2. It is not being traced by _you_, or 178 * 3. It is not currently stopped. 179 */ 180 if (t->p_pptr != p || t->p_stat != SSTOP || !t->p_waited) { 181 mutex_exit(t->p_lock); 182 mutex_exit(proc_lock); 183 error = EBUSY; 184 goto out; 185 } 186 mutex_exit(proc_lock); 187 /* XXX: ptrace needs revamp for multi-threading support. */ 188 if (t->p_nlwps > 1) { 189 mutex_exit(t->p_lock); 190 error = ENOSYS; 191 goto out; 192 } 193 lt = LIST_FIRST(&t->p_lwps); 194 *retval = 0; 195 196 switch (request) { 197 case LINUX_PTRACE_GETREGS: 198 error = process_read_regs(lt, regs); 199 mutex_exit(t->p_lock); 200 if (error) { 201 break; 202 } 203 for (i = 0; i <= 31; i++) { 204 linux_regs->lgpr[i] = regs->fixreg[i]; 205 } 206 linux_regs->lnip = regs->pc; 207 linux_regs->lmsr = 0; 208 /* XXX Is that right? */ 209 linux_regs->lorig_gpr3 = regs->fixreg[3]; 210 linux_regs->lctr = regs->ctr; 211 linux_regs->llink = regs->lr; 212 linux_regs->lxer = regs->xer; 213 linux_regs->lccr = regs->cr; 214 linux_regs->lmq = 0; 215 linux_regs->ltrap = 0; 216 linux_regs->ldar = 0; 217 linux_regs->ldsisr = 0; 218 linux_regs->lresult = 0; 219 220 error = copyout(linux_regs, (void *)SCARG(uap, data), 221 sizeof(struct linux_pt_regs)); 222 break; 223 224 case LINUX_PTRACE_SETREGS: 225 for (i = 0; i <= 31; i++) { 226 regs->fixreg[i] = linux_regs->lgpr[i]; 227 } 228 regs->lr = linux_regs->llink; 229 regs->cr = linux_regs->lccr; 230 regs->xer = linux_regs->lxer; 231 regs->ctr = linux_regs->lctr; 232 regs->pc = linux_regs->lnip; /* XXX */ 233 234 error = process_write_regs(lt, regs); 235 mutex_exit(t->p_lock); 236 break; 237 238 case LINUX_PTRACE_GETFPREGS: 239 error = process_read_fpregs(lt, fpregs, NULL); 240 mutex_exit(t->p_lock); 241 if (error) { 242 break; 243 } 244 /* Zero the contents if NetBSD fpreg structure is smaller */ 245 if (sizeof(struct fpreg) < (32 * sizeof(double))) { 246 memset(linux_fpreg, '\0', (32 * sizeof(double))); 247 } 248 memcpy(linux_fpreg, fpregs, 249 min(32 * sizeof(double), sizeof(struct fpreg))); 250 error = copyout(linux_fpreg, (void *)SCARG(uap, data), 251 32 * sizeof(double)); 252 break; 253 254 case LINUX_PTRACE_SETFPREGS: 255 memset(fpregs, '\0', sizeof(struct fpreg)); 256 memcpy(fpregs, linux_fpreg, 257 min(32 * sizeof(double), sizeof(struct fpreg))); 258 error = process_write_fpregs(lt, fpregs, sizeof fpregs); 259 mutex_exit(t->p_lock); 260 break; 261 262 case LINUX_PTRACE_PEEKUSR: 263 addr = SCARG(uap, addr); 264 error = process_read_regs(lt, regs); 265 mutex_exit(t->p_lock); 266 if (error) { 267 break; 268 } 269 error = 0; 270 if ((addr < LUSR_OFF(lusr_startgdb)) || 271 (addr > LUSR_OFF(lu_comm_end))) 272 error = 1; 273 else if (addr == LUSR_OFF(u_tsize)) 274 *retval = p->p_vmspace->vm_tsize; 275 else if (addr == LUSR_OFF(u_dsize)) 276 *retval = p->p_vmspace->vm_dsize; 277 else if (addr == LUSR_OFF(u_ssize)) 278 *retval = p->p_vmspace->vm_ssize; 279 else if (addr == LUSR_OFF(start_code)) 280 *retval = (register_t) p->p_vmspace->vm_taddr; 281 else if (addr == LUSR_OFF(start_stack)) 282 *retval = (register_t) p->p_vmspace->vm_minsaddr; 283 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 284 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 285 *retval = regs->fixreg[addr / sizeof (register_t)]; 286 else if (addr == LUSR_REG_OFF(lnip)) 287 *retval = regs->pc; 288 else if (addr == LUSR_REG_OFF(lctr)) 289 *retval = regs->ctr; 290 else if (addr == LUSR_REG_OFF(llink)) 291 *retval = regs->lr; 292 else if (addr == LUSR_REG_OFF(lxer)) 293 *retval = regs->xer; 294 else if (addr == LUSR_REG_OFF(lccr)) 295 *retval = regs->cr; 296 else if (addr == LUSR_OFF(signal)) 297 error = 1; 298 else if (addr == LUSR_OFF(magic)) 299 error = 1; 300 else if (addr == LUSR_OFF(u_comm)) 301 error = 1; 302 else { 303 #ifdef DEBUG_LINUX 304 printf("linux_ptrace: unsupported address: %d\n", addr); 305 #endif 306 error = 1; 307 } 308 if (error) { 309 break; 310 } 311 error = copyout (retval, (void *)SCARG(uap, data), 312 sizeof(retval)); 313 *retval = SCARG(uap, data); 314 break; 315 316 case LINUX_PTRACE_POKEUSR: /* XXX Not tested */ 317 addr = SCARG(uap, addr); 318 error = process_read_regs(lt, regs); 319 if (error) { 320 mutex_exit(t->p_lock); 321 break; 322 } 323 error = 0; 324 if ((addr < LUSR_OFF(lusr_startgdb)) || 325 (addr > LUSR_OFF(lu_comm_end))) 326 error = 1; 327 else if (addr == LUSR_OFF(u_tsize)) 328 error = 1; 329 else if (addr == LUSR_OFF(u_dsize)) 330 error = 1; 331 else if (addr == LUSR_OFF(u_ssize)) 332 error = 1; 333 else if (addr == LUSR_OFF(start_code)) 334 error = 1; 335 else if (addr == LUSR_OFF(start_stack)) 336 error = 1; 337 else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && 338 (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) 339 regs->fixreg[addr / sizeof (register_t)] = 340 (register_t)SCARG(uap, data); 341 else if (addr == LUSR_REG_OFF(lnip)) 342 regs->pc = (register_t)SCARG(uap, data); 343 else if (addr == LUSR_REG_OFF(lctr)) 344 regs->ctr = (register_t)SCARG(uap, data); 345 else if (addr == LUSR_REG_OFF(llink)) 346 regs->lr = (register_t)SCARG(uap, data); 347 else if (addr == LUSR_REG_OFF(lxer)) 348 regs->xer = (register_t)SCARG(uap, data); 349 else if (addr == LUSR_REG_OFF(lccr)) 350 regs->cr = (register_t)SCARG(uap, data); 351 else if (addr == LUSR_OFF(signal)) 352 error = 1; 353 else if (addr == LUSR_OFF(magic)) 354 error = 1; 355 else if (addr == LUSR_OFF(u_comm)) 356 error = 1; 357 else { 358 #ifdef DEBUG_LINUX 359 printf("linux_ptrace: unsupported address: %d\n", addr); 360 #endif 361 error = 1; 362 } 363 error = process_write_regs(lt,regs); 364 mutex_exit(t->p_lock); 365 break; 366 default: 367 mutex_exit(t->p_lock); 368 break; 369 } 370 out: 371 if (regs) 372 kmem_free(regs, sizeof(*regs)); 373 if (fpregs) 374 kmem_free(fpregs, sizeof(*fpregs)); 375 if (linux_regs) 376 kmem_free(linux_regs, sizeof(*linux_regs)); 377 if (linux_fpreg) 378 kmem_free(linux_fpreg, sizeof(*linux_fpreg)); 379 return error; 380 } 381
Indexes created Wed Sep 24 22:09:59 GMT 2025