sys_process.c revision 276686
1176491Smarcel/*- 2176491Smarcel * Copyright (c) 1994, Sean Eric Fagan 3331722Seadler * All rights reserved. 4176491Smarcel * 5176491Smarcel * Redistribution and use in source and binary forms, with or without 6176491Smarcel * modification, are permitted provided that the following conditions 7176491Smarcel * are met: 8176491Smarcel * 1. Redistributions of source code must retain the above copyright 9176491Smarcel * notice, this list of conditions and the following disclaimer. 10176491Smarcel * 2. Redistributions in binary form must reproduce the above copyright 11176491Smarcel * notice, this list of conditions and the following disclaimer in the 12176491Smarcel * documentation and/or other materials provided with the distribution. 13176491Smarcel * 3. All advertising materials mentioning features or use of this software 14176491Smarcel * must display the following acknowledgement: 15176491Smarcel * This product includes software developed by Sean Eric Fagan. 16176491Smarcel * 4. The name of the author may not be used to endorse or promote products 17176491Smarcel * derived from this software without specific prior written permission. 18176491Smarcel * 19176491Smarcel * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20176491Smarcel * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21176491Smarcel * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22176491Smarcel * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23176491Smarcel * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24176491Smarcel * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25176491Smarcel * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26176491Smarcel * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27176491Smarcel * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28176491Smarcel * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29176491Smarcel * SUCH DAMAGE. 30176491Smarcel */ 31176491Smarcel 32176491Smarcel#include <sys/cdefs.h> 33176491Smarcel__FBSDID("$FreeBSD: stable/10/sys/kern/sys_process.c 276686 2015-01-05 03:27:09Z kib $"); 34176491Smarcel 35176491Smarcel#include "opt_compat.h" 36176491Smarcel 37176491Smarcel#include <sys/param.h> 38176491Smarcel#include <sys/systm.h> 39176491Smarcel#include <sys/lock.h> 40176491Smarcel#include <sys/mutex.h> 41176491Smarcel#include <sys/syscallsubr.h> 42176491Smarcel#include <sys/sysent.h> 43176491Smarcel#include <sys/sysproto.h> 44176491Smarcel#include <sys/priv.h> 45176491Smarcel#include <sys/proc.h> 46176491Smarcel#include <sys/vnode.h> 47176491Smarcel#include <sys/ptrace.h> 48176491Smarcel#include <sys/rwlock.h> 49176491Smarcel#include <sys/sx.h> 50178030Sgrehan#include <sys/malloc.h> 51176491Smarcel#include <sys/signalvar.h> 52176491Smarcel 53176491Smarcel#include <machine/reg.h> 54176491Smarcel 55176491Smarcel#include <security/audit/audit.h> 56176491Smarcel 57176491Smarcel#include <vm/vm.h> 58176491Smarcel#include <vm/pmap.h> 59176491Smarcel#include <vm/vm_extern.h> 60176491Smarcel#include <vm/vm_map.h> 61176491Smarcel#include <vm/vm_kern.h> 62176491Smarcel#include <vm/vm_object.h> 63176491Smarcel#include <vm/vm_page.h> 64176491Smarcel#include <vm/vm_param.h> 65176491Smarcel 66176491Smarcel#ifdef COMPAT_FREEBSD32 67176491Smarcel#include <sys/procfs.h> 68176491Smarcel#include <compat/freebsd32/freebsd32_signal.h> 69176491Smarcel 70176491Smarcelstruct ptrace_io_desc32 { 71176491Smarcel int piod_op; 72176491Smarcel uint32_t piod_offs; 73176491Smarcel uint32_t piod_addr; 74176491Smarcel uint32_t piod_len; 75176491Smarcel}; 76176491Smarcel 77176491Smarcelstruct ptrace_vm_entry32 { 78176491Smarcel int pve_entry; 79176491Smarcel int pve_timestamp; 80176491Smarcel uint32_t pve_start; 81176491Smarcel uint32_t pve_end; 82176491Smarcel uint32_t pve_offset; 83176491Smarcel u_int pve_prot; 84176491Smarcel u_int pve_pathlen; 85176491Smarcel int32_t pve_fileid; 86176491Smarcel u_int pve_fsid; 87176491Smarcel uint32_t pve_path; 88176491Smarcel}; 89176491Smarcel 90176491Smarcelstruct ptrace_lwpinfo32 { 91176491Smarcel lwpid_t pl_lwpid; /* LWP described. */ 92176491Smarcel int pl_event; /* Event that stopped the LWP. */ 93176491Smarcel int pl_flags; /* LWP flags. */ 94176491Smarcel sigset_t pl_sigmask; /* LWP signal mask */ 95176491Smarcel sigset_t pl_siglist; /* LWP pending signal */ 96176491Smarcel struct siginfo32 pl_siginfo; /* siginfo for signal */ 97176491Smarcel char pl_tdname[MAXCOMLEN + 1]; /* LWP name. */ 98176491Smarcel int pl_child_pid; /* New child pid */ 99176491Smarcel}; 100176491Smarcel 101176491Smarcel#endif 102176491Smarcel 103176491Smarcel/* 104176491Smarcel * Functions implemented using PROC_ACTION(): 105176491Smarcel * 106176491Smarcel * proc_read_regs(proc, regs) 107176491Smarcel * Get the current user-visible register set from the process 108176491Smarcel * and copy it into the regs structure (<machine/reg.h>). 109176491Smarcel * The process is stopped at the time read_regs is called. 110176491Smarcel * 111176491Smarcel * proc_write_regs(proc, regs) 112176491Smarcel * Update the current register set from the passed in regs 113176491Smarcel * structure. Take care to avoid clobbering special CPU 114176491Smarcel * registers or privileged bits in the PSL. 115176491Smarcel * Depending on the architecture this may have fix-up work to do, 116176491Smarcel * especially if the IAR or PCW are modified. 117176491Smarcel * The process is stopped at the time write_regs is called. 118176491Smarcel * 119176491Smarcel * proc_read_fpregs, proc_write_fpregs 120176491Smarcel * deal with the floating point register set, otherwise as above. 121176491Smarcel * 122176491Smarcel * proc_read_dbregs, proc_write_dbregs 123176491Smarcel * deal with the processor debug register set, otherwise as above. 124176491Smarcel * 125176491Smarcel * proc_sstep(proc) 126176491Smarcel * Arrange for the process to trap after executing a single instruction. 127176491Smarcel */ 128176491Smarcel 129176491Smarcel#define PROC_ACTION(action) do { \ 130176491Smarcel int error; \ 131176491Smarcel \ 132176491Smarcel PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); \ 133176491Smarcel if ((td->td_proc->p_flag & P_INMEM) == 0) \ 134176491Smarcel error = EIO; \ 135176491Smarcel else \ 136176491Smarcel error = (action); \ 137176491Smarcel return (error); \ 138176491Smarcel} while(0) 139176491Smarcel 140176491Smarcelint 141176491Smarcelproc_read_regs(struct thread *td, struct reg *regs) 142176491Smarcel{ 143176491Smarcel 144176491Smarcel PROC_ACTION(fill_regs(td, regs)); 145176491Smarcel} 146176491Smarcel 147176491Smarcelint 148176491Smarcelproc_write_regs(struct thread *td, struct reg *regs) 149176491Smarcel{ 150176491Smarcel 151176491Smarcel PROC_ACTION(set_regs(td, regs)); 152176491Smarcel} 153176491Smarcel 154176491Smarcelint 155176491Smarcelproc_read_dbregs(struct thread *td, struct dbreg *dbregs) 156176491Smarcel{ 157176491Smarcel 158176491Smarcel PROC_ACTION(fill_dbregs(td, dbregs)); 159176491Smarcel} 160176491Smarcel 161176491Smarcelint 162176491Smarcelproc_write_dbregs(struct thread *td, struct dbreg *dbregs) 163176491Smarcel{ 164176491Smarcel 165176491Smarcel PROC_ACTION(set_dbregs(td, dbregs)); 166176491Smarcel} 167176491Smarcel 168176491Smarcel/* 169176491Smarcel * Ptrace doesn't support fpregs at all, and there are no security holes 170176491Smarcel * or translations for fpregs, so we can just copy them. 171176491Smarcel */ 172176491Smarcelint 173176491Smarcelproc_read_fpregs(struct thread *td, struct fpreg *fpregs) 174176491Smarcel{ 175176491Smarcel 176176491Smarcel PROC_ACTION(fill_fpregs(td, fpregs)); 177176491Smarcel} 178176491Smarcel 179176491Smarcelint 180176491Smarcelproc_write_fpregs(struct thread *td, struct fpreg *fpregs) 181176491Smarcel{ 182176491Smarcel 183176491Smarcel PROC_ACTION(set_fpregs(td, fpregs)); 184176491Smarcel} 185176491Smarcel 186176491Smarcel#ifdef COMPAT_FREEBSD32 187176491Smarcel/* For 32 bit binaries, we need to expose the 32 bit regs layouts. */ 188176491Smarcelint 189176491Smarcelproc_read_regs32(struct thread *td, struct reg32 *regs32) 190176491Smarcel{ 191176491Smarcel 192176491Smarcel PROC_ACTION(fill_regs32(td, regs32)); 193176491Smarcel} 194176491Smarcel 195176491Smarcelint 196176491Smarcelproc_write_regs32(struct thread *td, struct reg32 *regs32) 197176491Smarcel{ 198176491Smarcel 199176491Smarcel PROC_ACTION(set_regs32(td, regs32)); 200176491Smarcel} 201176491Smarcel 202176491Smarcelint 203176491Smarcelproc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 204176491Smarcel{ 205176491Smarcel 206176491Smarcel PROC_ACTION(fill_dbregs32(td, dbregs32)); 207176491Smarcel} 208176491Smarcel 209176491Smarcelint 210176491Smarcelproc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32) 211176491Smarcel{ 212176491Smarcel 213176491Smarcel PROC_ACTION(set_dbregs32(td, dbregs32)); 214176491Smarcel} 215176491Smarcel 216176491Smarcelint 217176491Smarcelproc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 218176491Smarcel{ 219176491Smarcel 220176491Smarcel PROC_ACTION(fill_fpregs32(td, fpregs32)); 221176491Smarcel} 222176491Smarcel 223176491Smarcelint 224176491Smarcelproc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32) 225176491Smarcel{ 226176491Smarcel 227176491Smarcel PROC_ACTION(set_fpregs32(td, fpregs32)); 228176491Smarcel} 229176491Smarcel#endif 230176491Smarcel 231176491Smarcelint 232176491Smarcelproc_sstep(struct thread *td) 233176491Smarcel{ 234176491Smarcel 235176491Smarcel PROC_ACTION(ptrace_single_step(td)); 236176491Smarcel} 237176491Smarcel 238176491Smarcelint 239176491Smarcelproc_rwmem(struct proc *p, struct uio *uio) 240176491Smarcel{ 241176491Smarcel vm_map_t map; 242176491Smarcel vm_offset_t pageno; /* page number */ 243176491Smarcel vm_prot_t reqprot; 244176491Smarcel int error, fault_flags, page_offset, writing; 245176491Smarcel 246176491Smarcel /* 247176491Smarcel * Assert that someone has locked this vmspace. (Should be 248176491Smarcel * curthread but we can't assert that.) This keeps the process 249176491Smarcel * from exiting out from under us until this operation completes. 250176491Smarcel */ 251176491Smarcel KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__, 252176491Smarcel p, p->p_pid)); 253176491Smarcel 254176491Smarcel /* 255176491Smarcel * The map we want... 256176491Smarcel */ 257176491Smarcel map = &p->p_vmspace->vm_map; 258176491Smarcel 259176491Smarcel /* 260176491Smarcel * If we are writing, then we request vm_fault() to create a private 261176491Smarcel * copy of each page. Since these copies will not be writeable by the 262176491Smarcel * process, we must explicity request that they be dirtied. 263176491Smarcel */ 264176491Smarcel writing = uio->uio_rw == UIO_WRITE; 265176491Smarcel reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ; 266176491Smarcel fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 267176491Smarcel 268176491Smarcel /* 269176491Smarcel * Only map in one page at a time. We don't have to, but it 270176491Smarcel * makes things easier. This way is trivial - right? 271176491Smarcel */ 272176491Smarcel do { 273176491Smarcel vm_offset_t uva; 274176491Smarcel u_int len; 275176491Smarcel vm_page_t m; 276176491Smarcel 277258780Seadler uva = (vm_offset_t)uio->uio_offset; 278176491Smarcel 279176491Smarcel /* 280176491Smarcel * Get the page number of this segment. 281176491Smarcel */ 282176491Smarcel pageno = trunc_page(uva); 283176491Smarcel page_offset = uva - pageno; 284176491Smarcel 285176491Smarcel /* 286176491Smarcel * How many bytes to copy 287176491Smarcel */ 288176491Smarcel len = min(PAGE_SIZE - page_offset, uio->uio_resid); 289176491Smarcel 290176491Smarcel /* 291176491Smarcel * Fault and hold the page on behalf of the process. 292176491Smarcel */ 293176491Smarcel error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m); 294176491Smarcel if (error != KERN_SUCCESS) { 295176491Smarcel if (error == KERN_RESOURCE_SHORTAGE) 296176491Smarcel error = ENOMEM; 297176491Smarcel else 298176491Smarcel error = EFAULT; 299176491Smarcel break; 300176491Smarcel } 301176491Smarcel 302176491Smarcel /* 303176491Smarcel * Now do the i/o move. 304176491Smarcel */ 305176491Smarcel error = uiomove_fromphys(&m, page_offset, len, uio); 306176491Smarcel 307176491Smarcel /* Make the I-cache coherent for breakpoints. */ 308176491Smarcel if (writing && error == 0) { 309176491Smarcel vm_map_lock_read(map); 310176491Smarcel if (vm_map_check_protection(map, pageno, pageno + 311176491Smarcel PAGE_SIZE, VM_PROT_EXECUTE)) 312176491Smarcel vm_sync_icache(map, uva, len); 313176491Smarcel vm_map_unlock_read(map); 314176491Smarcel } 315176491Smarcel 316176491Smarcel /* 317176491Smarcel * Release the page. 318176491Smarcel */ 319176491Smarcel vm_page_lock(m); 320176491Smarcel vm_page_unhold(m); 321176491Smarcel vm_page_unlock(m); 322176491Smarcel 323176491Smarcel } while (error == 0 && uio->uio_resid > 0); 324176491Smarcel 325176491Smarcel return (error); 326176491Smarcel} 327176491Smarcel 328176491Smarcelstatic int 329176491Smarcelptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve) 330176491Smarcel{ 331176491Smarcel struct vattr vattr; 332176491Smarcel vm_map_t map; 333176491Smarcel vm_map_entry_t entry; 334176491Smarcel vm_object_t obj, tobj, lobj; 335176491Smarcel struct vmspace *vm; 336176491Smarcel struct vnode *vp; 337176491Smarcel char *freepath, *fullpath; 338176491Smarcel u_int pathlen; 339176491Smarcel int error, index; 340176491Smarcel 341176491Smarcel error = 0; 342176491Smarcel obj = NULL; 343176491Smarcel 344176491Smarcel vm = vmspace_acquire_ref(p); 345176491Smarcel map = &vm->vm_map; 346176491Smarcel vm_map_lock_read(map); 347176491Smarcel 348176491Smarcel do { 349176491Smarcel entry = map->header.next; 350176491Smarcel index = 0; 351176491Smarcel while (index < pve->pve_entry && entry != &map->header) { 352176491Smarcel entry = entry->next; 353176491Smarcel index++; 354176491Smarcel } 355176491Smarcel if (index != pve->pve_entry) { 356176491Smarcel error = EINVAL; 357176491Smarcel break; 358176491Smarcel } 359176491Smarcel while (entry != &map->header && 360176491Smarcel (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) { 361176491Smarcel entry = entry->next; 362176491Smarcel index++; 363176491Smarcel } 364176491Smarcel if (entry == &map->header) { 365176491Smarcel error = ENOENT; 366176491Smarcel break; 367176491Smarcel } 368176491Smarcel 369176491Smarcel /* We got an entry. */ 370176491Smarcel pve->pve_entry = index + 1; 371176491Smarcel pve->pve_timestamp = map->timestamp; 372176491Smarcel pve->pve_start = entry->start; 373176491Smarcel pve->pve_end = entry->end - 1; 374176491Smarcel pve->pve_offset = entry->offset; 375176491Smarcel pve->pve_prot = entry->protection; 376176491Smarcel 377176491Smarcel /* Backing object's path needed? */ 378176491Smarcel if (pve->pve_pathlen == 0) 379176491Smarcel break; 380176491Smarcel 381176491Smarcel pathlen = pve->pve_pathlen; 382176491Smarcel pve->pve_pathlen = 0; 383176491Smarcel 384176491Smarcel obj = entry->object.vm_object; 385176491Smarcel if (obj != NULL) 386176491Smarcel VM_OBJECT_RLOCK(obj); 387176491Smarcel } while (0); 388176491Smarcel 389176491Smarcel vm_map_unlock_read(map); 390176491Smarcel vmspace_free(vm); 391176491Smarcel 392176491Smarcel pve->pve_fsid = VNOVAL; 393176491Smarcel pve->pve_fileid = VNOVAL; 394176491Smarcel 395176491Smarcel if (error == 0 && obj != NULL) { 396176491Smarcel lobj = obj; 397176491Smarcel for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 398176491Smarcel if (tobj != obj) 399176491Smarcel VM_OBJECT_RLOCK(tobj); 400176491Smarcel if (lobj != obj) 401176491Smarcel VM_OBJECT_RUNLOCK(lobj); 402176491Smarcel lobj = tobj; 403176491Smarcel pve->pve_offset += tobj->backing_object_offset; 404176491Smarcel } 405176491Smarcel vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL; 406176491Smarcel if (vp != NULL) 407176491Smarcel vref(vp); 408176491Smarcel if (lobj != obj) 409176491Smarcel VM_OBJECT_RUNLOCK(lobj); 410176491Smarcel VM_OBJECT_RUNLOCK(obj); 411176491Smarcel 412176491Smarcel if (vp != NULL) { 413176491Smarcel freepath = NULL; 414176491Smarcel fullpath = NULL; 415176491Smarcel vn_fullpath(td, vp, &fullpath, &freepath); 416 vn_lock(vp, LK_SHARED | LK_RETRY); 417 if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) { 418 pve->pve_fileid = vattr.va_fileid; 419 pve->pve_fsid = vattr.va_fsid; 420 } 421 vput(vp); 422 423 if (fullpath != NULL) { 424 pve->pve_pathlen = strlen(fullpath) + 1; 425 if (pve->pve_pathlen <= pathlen) { 426 error = copyout(fullpath, pve->pve_path, 427 pve->pve_pathlen); 428 } else 429 error = ENAMETOOLONG; 430 } 431 if (freepath != NULL) 432 free(freepath, M_TEMP); 433 } 434 } 435 436 return (error); 437} 438 439#ifdef COMPAT_FREEBSD32 440static int 441ptrace_vm_entry32(struct thread *td, struct proc *p, 442 struct ptrace_vm_entry32 *pve32) 443{ 444 struct ptrace_vm_entry pve; 445 int error; 446 447 pve.pve_entry = pve32->pve_entry; 448 pve.pve_pathlen = pve32->pve_pathlen; 449 pve.pve_path = (void *)(uintptr_t)pve32->pve_path; 450 451 error = ptrace_vm_entry(td, p, &pve); 452 if (error == 0) { 453 pve32->pve_entry = pve.pve_entry; 454 pve32->pve_timestamp = pve.pve_timestamp; 455 pve32->pve_start = pve.pve_start; 456 pve32->pve_end = pve.pve_end; 457 pve32->pve_offset = pve.pve_offset; 458 pve32->pve_prot = pve.pve_prot; 459 pve32->pve_fileid = pve.pve_fileid; 460 pve32->pve_fsid = pve.pve_fsid; 461 } 462 463 pve32->pve_pathlen = pve.pve_pathlen; 464 return (error); 465} 466 467static void 468ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl, 469 struct ptrace_lwpinfo32 *pl32) 470{ 471 472 pl32->pl_lwpid = pl->pl_lwpid; 473 pl32->pl_event = pl->pl_event; 474 pl32->pl_flags = pl->pl_flags; 475 pl32->pl_sigmask = pl->pl_sigmask; 476 pl32->pl_siglist = pl->pl_siglist; 477 siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo); 478 strcpy(pl32->pl_tdname, pl->pl_tdname); 479 pl32->pl_child_pid = pl->pl_child_pid; 480} 481#endif /* COMPAT_FREEBSD32 */ 482 483/* 484 * Process debugging system call. 485 */ 486#ifndef _SYS_SYSPROTO_H_ 487struct ptrace_args { 488 int req; 489 pid_t pid; 490 caddr_t addr; 491 int data; 492}; 493#endif 494 495#ifdef COMPAT_FREEBSD32 496/* 497 * This CPP subterfuge is to try and reduce the number of ifdefs in 498 * the body of the code. 499 * COPYIN(uap->addr, &r.reg, sizeof r.reg); 500 * becomes either: 501 * copyin(uap->addr, &r.reg, sizeof r.reg); 502 * or 503 * copyin(uap->addr, &r.reg32, sizeof r.reg32); 504 * .. except this is done at runtime. 505 */ 506#define COPYIN(u, k, s) wrap32 ? \ 507 copyin(u, k ## 32, s ## 32) : \ 508 copyin(u, k, s) 509#define COPYOUT(k, u, s) wrap32 ? \ 510 copyout(k ## 32, u, s ## 32) : \ 511 copyout(k, u, s) 512#else 513#define COPYIN(u, k, s) copyin(u, k, s) 514#define COPYOUT(k, u, s) copyout(k, u, s) 515#endif 516int 517sys_ptrace(struct thread *td, struct ptrace_args *uap) 518{ 519 /* 520 * XXX this obfuscation is to reduce stack usage, but the register 521 * structs may be too large to put on the stack anyway. 522 */ 523 union { 524 struct ptrace_io_desc piod; 525 struct ptrace_lwpinfo pl; 526 struct ptrace_vm_entry pve; 527 struct dbreg dbreg; 528 struct fpreg fpreg; 529 struct reg reg; 530#ifdef COMPAT_FREEBSD32 531 struct dbreg32 dbreg32; 532 struct fpreg32 fpreg32; 533 struct reg32 reg32; 534 struct ptrace_io_desc32 piod32; 535 struct ptrace_lwpinfo32 pl32; 536 struct ptrace_vm_entry32 pve32; 537#endif 538 } r; 539 void *addr; 540 int error = 0; 541#ifdef COMPAT_FREEBSD32 542 int wrap32 = 0; 543 544 if (SV_CURPROC_FLAG(SV_ILP32)) 545 wrap32 = 1; 546#endif 547 AUDIT_ARG_PID(uap->pid); 548 AUDIT_ARG_CMD(uap->req); 549 AUDIT_ARG_VALUE(uap->data); 550 addr = &r; 551 switch (uap->req) { 552 case PT_GETREGS: 553 case PT_GETFPREGS: 554 case PT_GETDBREGS: 555 case PT_LWPINFO: 556 break; 557 case PT_SETREGS: 558 error = COPYIN(uap->addr, &r.reg, sizeof r.reg); 559 break; 560 case PT_SETFPREGS: 561 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg); 562 break; 563 case PT_SETDBREGS: 564 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg); 565 break; 566 case PT_IO: 567 error = COPYIN(uap->addr, &r.piod, sizeof r.piod); 568 break; 569 case PT_VM_ENTRY: 570 error = COPYIN(uap->addr, &r.pve, sizeof r.pve); 571 break; 572 default: 573 addr = uap->addr; 574 break; 575 } 576 if (error) 577 return (error); 578 579 error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data); 580 if (error) 581 return (error); 582 583 switch (uap->req) { 584 case PT_VM_ENTRY: 585 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve); 586 break; 587 case PT_IO: 588 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod); 589 break; 590 case PT_GETREGS: 591 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg); 592 break; 593 case PT_GETFPREGS: 594 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg); 595 break; 596 case PT_GETDBREGS: 597 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg); 598 break; 599 case PT_LWPINFO: 600 error = copyout(&r.pl, uap->addr, uap->data); 601 break; 602 } 603 604 return (error); 605} 606#undef COPYIN 607#undef COPYOUT 608 609#ifdef COMPAT_FREEBSD32 610/* 611 * PROC_READ(regs, td2, addr); 612 * becomes either: 613 * proc_read_regs(td2, addr); 614 * or 615 * proc_read_regs32(td2, addr); 616 * .. except this is done at runtime. There is an additional 617 * complication in that PROC_WRITE disallows 32 bit consumers 618 * from writing to 64 bit address space targets. 619 */ 620#define PROC_READ(w, t, a) wrap32 ? \ 621 proc_read_ ## w ## 32(t, a) : \ 622 proc_read_ ## w (t, a) 623#define PROC_WRITE(w, t, a) wrap32 ? \ 624 (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \ 625 proc_write_ ## w (t, a) 626#else 627#define PROC_READ(w, t, a) proc_read_ ## w (t, a) 628#define PROC_WRITE(w, t, a) proc_write_ ## w (t, a) 629#endif 630 631int 632kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 633{ 634 struct iovec iov; 635 struct uio uio; 636 struct proc *curp, *p, *pp; 637 struct thread *td2 = NULL, *td3; 638 struct ptrace_io_desc *piod = NULL; 639 struct ptrace_lwpinfo *pl; 640 int error, write, tmp, num; 641 int proctree_locked = 0; 642 lwpid_t tid = 0, *buf; 643#ifdef COMPAT_FREEBSD32 644 int wrap32 = 0, safe = 0; 645 struct ptrace_io_desc32 *piod32 = NULL; 646 struct ptrace_lwpinfo32 *pl32 = NULL; 647 struct ptrace_lwpinfo plr; 648#endif 649 650 curp = td->td_proc; 651 652 /* Lock proctree before locking the process. */ 653 switch (req) { 654 case PT_TRACE_ME: 655 case PT_ATTACH: 656 case PT_STEP: 657 case PT_CONTINUE: 658 case PT_TO_SCE: 659 case PT_TO_SCX: 660 case PT_SYSCALL: 661 case PT_FOLLOW_FORK: 662 case PT_DETACH: 663 sx_xlock(&proctree_lock); 664 proctree_locked = 1; 665 break; 666 default: 667 break; 668 } 669 670 write = 0; 671 if (req == PT_TRACE_ME) { 672 p = td->td_proc; 673 PROC_LOCK(p); 674 } else { 675 if (pid <= PID_MAX) { 676 if ((p = pfind(pid)) == NULL) { 677 if (proctree_locked) 678 sx_xunlock(&proctree_lock); 679 return (ESRCH); 680 } 681 } else { 682 td2 = tdfind(pid, -1); 683 if (td2 == NULL) { 684 if (proctree_locked) 685 sx_xunlock(&proctree_lock); 686 return (ESRCH); 687 } 688 p = td2->td_proc; 689 tid = pid; 690 pid = p->p_pid; 691 } 692 } 693 AUDIT_ARG_PROCESS(p); 694 695 if ((p->p_flag & P_WEXIT) != 0) { 696 error = ESRCH; 697 goto fail; 698 } 699 if ((error = p_cansee(td, p)) != 0) 700 goto fail; 701 702 if ((error = p_candebug(td, p)) != 0) 703 goto fail; 704 705 /* 706 * System processes can't be debugged. 707 */ 708 if ((p->p_flag & P_SYSTEM) != 0) { 709 error = EINVAL; 710 goto fail; 711 } 712 713 if (tid == 0) { 714 if ((p->p_flag & P_STOPPED_TRACE) != 0) { 715 KASSERT(p->p_xthread != NULL, ("NULL p_xthread")); 716 td2 = p->p_xthread; 717 } else { 718 td2 = FIRST_THREAD_IN_PROC(p); 719 } 720 tid = td2->td_tid; 721 } 722 723#ifdef COMPAT_FREEBSD32 724 /* 725 * Test if we're a 32 bit client and what the target is. 726 * Set the wrap controls accordingly. 727 */ 728 if (SV_CURPROC_FLAG(SV_ILP32)) { 729 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32)) 730 safe = 1; 731 wrap32 = 1; 732 } 733#endif 734 /* 735 * Permissions check 736 */ 737 switch (req) { 738 case PT_TRACE_ME: 739 /* Always legal. */ 740 break; 741 742 case PT_ATTACH: 743 /* Self */ 744 if (p->p_pid == td->td_proc->p_pid) { 745 error = EINVAL; 746 goto fail; 747 } 748 749 /* Already traced */ 750 if (p->p_flag & P_TRACED) { 751 error = EBUSY; 752 goto fail; 753 } 754 755 /* Can't trace an ancestor if you're being traced. */ 756 if (curp->p_flag & P_TRACED) { 757 for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) { 758 if (pp == p) { 759 error = EINVAL; 760 goto fail; 761 } 762 } 763 } 764 765 766 /* OK */ 767 break; 768 769 case PT_CLEARSTEP: 770 /* Allow thread to clear single step for itself */ 771 if (td->td_tid == tid) 772 break; 773 774 /* FALLTHROUGH */ 775 default: 776 /* not being traced... */ 777 if ((p->p_flag & P_TRACED) == 0) { 778 error = EPERM; 779 goto fail; 780 } 781 782 /* not being traced by YOU */ 783 if (p->p_pptr != td->td_proc) { 784 error = EBUSY; 785 goto fail; 786 } 787 788 /* not currently stopped */ 789 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 || 790 p->p_suspcount != p->p_numthreads || 791 (p->p_flag & P_WAITED) == 0) { 792 error = EBUSY; 793 goto fail; 794 } 795 796 if ((p->p_flag & P_STOPPED_TRACE) == 0) { 797 static int count = 0; 798 if (count++ == 0) 799 printf("P_STOPPED_TRACE not set.\n"); 800 } 801 802 /* OK */ 803 break; 804 } 805 806 /* Keep this process around until we finish this request. */ 807 _PHOLD(p); 808 809#ifdef FIX_SSTEP 810 /* 811 * Single step fixup ala procfs 812 */ 813 FIX_SSTEP(td2); 814#endif 815 816 /* 817 * Actually do the requests 818 */ 819 820 td->td_retval[0] = 0; 821 822 switch (req) { 823 case PT_TRACE_ME: 824 /* set my trace flag and "owner" so it can read/write me */ 825 p->p_flag |= P_TRACED; 826 if (p->p_flag & P_PPWAIT) 827 p->p_flag |= P_PPTRACE; 828 p->p_oppid = p->p_pptr->p_pid; 829 break; 830 831 case PT_ATTACH: 832 /* security check done above */ 833 /* 834 * It would be nice if the tracing relationship was separate 835 * from the parent relationship but that would require 836 * another set of links in the proc struct or for "wait" 837 * to scan the entire proc table. To make life easier, 838 * we just re-parent the process we're trying to trace. 839 * The old parent is remembered so we can put things back 840 * on a "detach". 841 */ 842 p->p_flag |= P_TRACED; 843 p->p_oppid = p->p_pptr->p_pid; 844 if (p->p_pptr != td->td_proc) { 845 proc_reparent(p, td->td_proc); 846 } 847 data = SIGSTOP; 848 goto sendsig; /* in PT_CONTINUE below */ 849 850 case PT_CLEARSTEP: 851 error = ptrace_clear_single_step(td2); 852 break; 853 854 case PT_SETSTEP: 855 error = ptrace_single_step(td2); 856 break; 857 858 case PT_SUSPEND: 859 td2->td_dbgflags |= TDB_SUSPEND; 860 thread_lock(td2); 861 td2->td_flags |= TDF_NEEDSUSPCHK; 862 thread_unlock(td2); 863 break; 864 865 case PT_RESUME: 866 td2->td_dbgflags &= ~TDB_SUSPEND; 867 break; 868 869 case PT_FOLLOW_FORK: 870 if (data) 871 p->p_flag |= P_FOLLOWFORK; 872 else 873 p->p_flag &= ~P_FOLLOWFORK; 874 break; 875 876 case PT_STEP: 877 case PT_CONTINUE: 878 case PT_TO_SCE: 879 case PT_TO_SCX: 880 case PT_SYSCALL: 881 case PT_DETACH: 882 /* Zero means do not send any signal */ 883 if (data < 0 || data > _SIG_MAXSIG) { 884 error = EINVAL; 885 break; 886 } 887 888 switch (req) { 889 case PT_STEP: 890 error = ptrace_single_step(td2); 891 if (error) 892 goto out; 893 break; 894 case PT_CONTINUE: 895 case PT_TO_SCE: 896 case PT_TO_SCX: 897 case PT_SYSCALL: 898 if (addr != (void *)1) { 899 error = ptrace_set_pc(td2, 900 (u_long)(uintfptr_t)addr); 901 if (error) 902 goto out; 903 } 904 switch (req) { 905 case PT_TO_SCE: 906 p->p_stops |= S_PT_SCE; 907 break; 908 case PT_TO_SCX: 909 p->p_stops |= S_PT_SCX; 910 break; 911 case PT_SYSCALL: 912 p->p_stops |= S_PT_SCE | S_PT_SCX; 913 break; 914 } 915 break; 916 case PT_DETACH: 917 /* reset process parent */ 918 if (p->p_oppid != p->p_pptr->p_pid) { 919 PROC_LOCK(p->p_pptr); 920 sigqueue_take(p->p_ksi); 921 PROC_UNLOCK(p->p_pptr); 922 923 pp = proc_realparent(p); 924 proc_reparent(p, pp); 925 if (pp == initproc) 926 p->p_sigparent = SIGCHLD; 927 } 928 p->p_oppid = 0; 929 p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK); 930 931 /* should we send SIGCHLD? */ 932 /* childproc_continued(p); */ 933 break; 934 } 935 936 sendsig: 937 if (proctree_locked) { 938 sx_xunlock(&proctree_lock); 939 proctree_locked = 0; 940 } 941 p->p_xstat = data; 942 p->p_xthread = NULL; 943 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) { 944 /* deliver or queue signal */ 945 td2->td_dbgflags &= ~TDB_XSIG; 946 td2->td_xsig = data; 947 948 if (req == PT_DETACH) { 949 FOREACH_THREAD_IN_PROC(p, td3) 950 td3->td_dbgflags &= ~TDB_SUSPEND; 951 } 952 /* 953 * unsuspend all threads, to not let a thread run, 954 * you should use PT_SUSPEND to suspend it before 955 * continuing process. 956 */ 957 PROC_SLOCK(p); 958 p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED); 959 thread_unsuspend(p); 960 PROC_SUNLOCK(p); 961 if (req == PT_ATTACH) 962 kern_psignal(p, data); 963 } else { 964 if (data) 965 kern_psignal(p, data); 966 } 967 break; 968 969 case PT_WRITE_I: 970 case PT_WRITE_D: 971 td2->td_dbgflags |= TDB_USERWR; 972 write = 1; 973 /* FALLTHROUGH */ 974 case PT_READ_I: 975 case PT_READ_D: 976 PROC_UNLOCK(p); 977 tmp = 0; 978 /* write = 0 set above */ 979 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp; 980 iov.iov_len = sizeof(int); 981 uio.uio_iov = &iov; 982 uio.uio_iovcnt = 1; 983 uio.uio_offset = (off_t)(uintptr_t)addr; 984 uio.uio_resid = sizeof(int); 985 uio.uio_segflg = UIO_SYSSPACE; /* i.e.: the uap */ 986 uio.uio_rw = write ? UIO_WRITE : UIO_READ; 987 uio.uio_td = td; 988 error = proc_rwmem(p, &uio); 989 if (uio.uio_resid != 0) { 990 /* 991 * XXX proc_rwmem() doesn't currently return ENOSPC, 992 * so I think write() can bogusly return 0. 993 * XXX what happens for short writes? We don't want 994 * to write partial data. 995 * XXX proc_rwmem() returns EPERM for other invalid 996 * addresses. Convert this to EINVAL. Does this 997 * clobber returns of EPERM for other reasons? 998 */ 999 if (error == 0 || error == ENOSPC || error == EPERM) 1000 error = EINVAL; /* EOF */ 1001 } 1002 if (!write) 1003 td->td_retval[0] = tmp; 1004 PROC_LOCK(p); 1005 break; 1006 1007 case PT_IO: 1008#ifdef COMPAT_FREEBSD32 1009 if (wrap32) { 1010 piod32 = addr; 1011 iov.iov_base = (void *)(uintptr_t)piod32->piod_addr; 1012 iov.iov_len = piod32->piod_len; 1013 uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs; 1014 uio.uio_resid = piod32->piod_len; 1015 } else 1016#endif 1017 { 1018 piod = addr; 1019 iov.iov_base = piod->piod_addr; 1020 iov.iov_len = piod->piod_len; 1021 uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs; 1022 uio.uio_resid = piod->piod_len; 1023 } 1024 uio.uio_iov = &iov; 1025 uio.uio_iovcnt = 1; 1026 uio.uio_segflg = UIO_USERSPACE; 1027 uio.uio_td = td; 1028#ifdef COMPAT_FREEBSD32 1029 tmp = wrap32 ? piod32->piod_op : piod->piod_op; 1030#else 1031 tmp = piod->piod_op; 1032#endif 1033 switch (tmp) { 1034 case PIOD_READ_D: 1035 case PIOD_READ_I: 1036 uio.uio_rw = UIO_READ; 1037 break; 1038 case PIOD_WRITE_D: 1039 case PIOD_WRITE_I: 1040 td2->td_dbgflags |= TDB_USERWR; 1041 uio.uio_rw = UIO_WRITE; 1042 break; 1043 default: 1044 error = EINVAL; 1045 goto out; 1046 } 1047 PROC_UNLOCK(p); 1048 error = proc_rwmem(p, &uio); 1049#ifdef COMPAT_FREEBSD32 1050 if (wrap32) 1051 piod32->piod_len -= uio.uio_resid; 1052 else 1053#endif 1054 piod->piod_len -= uio.uio_resid; 1055 PROC_LOCK(p); 1056 break; 1057 1058 case PT_KILL: 1059 data = SIGKILL; 1060 goto sendsig; /* in PT_CONTINUE above */ 1061 1062 case PT_SETREGS: 1063 td2->td_dbgflags |= TDB_USERWR; 1064 error = PROC_WRITE(regs, td2, addr); 1065 break; 1066 1067 case PT_GETREGS: 1068 error = PROC_READ(regs, td2, addr); 1069 break; 1070 1071 case PT_SETFPREGS: 1072 td2->td_dbgflags |= TDB_USERWR; 1073 error = PROC_WRITE(fpregs, td2, addr); 1074 break; 1075 1076 case PT_GETFPREGS: 1077 error = PROC_READ(fpregs, td2, addr); 1078 break; 1079 1080 case PT_SETDBREGS: 1081 td2->td_dbgflags |= TDB_USERWR; 1082 error = PROC_WRITE(dbregs, td2, addr); 1083 break; 1084 1085 case PT_GETDBREGS: 1086 error = PROC_READ(dbregs, td2, addr); 1087 break; 1088 1089 case PT_LWPINFO: 1090 if (data <= 0 || 1091#ifdef COMPAT_FREEBSD32 1092 (!wrap32 && data > sizeof(*pl)) || 1093 (wrap32 && data > sizeof(*pl32))) { 1094#else 1095 data > sizeof(*pl)) { 1096#endif 1097 error = EINVAL; 1098 break; 1099 } 1100#ifdef COMPAT_FREEBSD32 1101 if (wrap32) { 1102 pl = &plr; 1103 pl32 = addr; 1104 } else 1105#endif 1106 pl = addr; 1107 pl->pl_lwpid = td2->td_tid; 1108 pl->pl_event = PL_EVENT_NONE; 1109 pl->pl_flags = 0; 1110 if (td2->td_dbgflags & TDB_XSIG) { 1111 pl->pl_event = PL_EVENT_SIGNAL; 1112 if (td2->td_dbgksi.ksi_signo != 0 && 1113#ifdef COMPAT_FREEBSD32 1114 ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo, 1115 pl_siginfo) + sizeof(pl->pl_siginfo)) || 1116 (wrap32 && data >= offsetof(struct ptrace_lwpinfo32, 1117 pl_siginfo) + sizeof(struct siginfo32))) 1118#else 1119 data >= offsetof(struct ptrace_lwpinfo, pl_siginfo) 1120 + sizeof(pl->pl_siginfo) 1121#endif 1122 ){ 1123 pl->pl_flags |= PL_FLAG_SI; 1124 pl->pl_siginfo = td2->td_dbgksi.ksi_info; 1125 } 1126 } 1127 if ((pl->pl_flags & PL_FLAG_SI) == 0) 1128 bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo)); 1129 if (td2->td_dbgflags & TDB_SCE) 1130 pl->pl_flags |= PL_FLAG_SCE; 1131 else if (td2->td_dbgflags & TDB_SCX) 1132 pl->pl_flags |= PL_FLAG_SCX; 1133 if (td2->td_dbgflags & TDB_EXEC) 1134 pl->pl_flags |= PL_FLAG_EXEC; 1135 if (td2->td_dbgflags & TDB_FORK) { 1136 pl->pl_flags |= PL_FLAG_FORKED; 1137 pl->pl_child_pid = td2->td_dbg_forked; 1138 } 1139 if (td2->td_dbgflags & TDB_CHILD) 1140 pl->pl_flags |= PL_FLAG_CHILD; 1141 pl->pl_sigmask = td2->td_sigmask; 1142 pl->pl_siglist = td2->td_siglist; 1143 strcpy(pl->pl_tdname, td2->td_name); 1144#ifdef COMPAT_FREEBSD32 1145 if (wrap32) 1146 ptrace_lwpinfo_to32(pl, pl32); 1147#endif 1148 break; 1149 1150 case PT_GETNUMLWPS: 1151 td->td_retval[0] = p->p_numthreads; 1152 break; 1153 1154 case PT_GETLWPLIST: 1155 if (data <= 0) { 1156 error = EINVAL; 1157 break; 1158 } 1159 num = imin(p->p_numthreads, data); 1160 PROC_UNLOCK(p); 1161 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK); 1162 tmp = 0; 1163 PROC_LOCK(p); 1164 FOREACH_THREAD_IN_PROC(p, td2) { 1165 if (tmp >= num) 1166 break; 1167 buf[tmp++] = td2->td_tid; 1168 } 1169 PROC_UNLOCK(p); 1170 error = copyout(buf, addr, tmp * sizeof(lwpid_t)); 1171 free(buf, M_TEMP); 1172 if (!error) 1173 td->td_retval[0] = tmp; 1174 PROC_LOCK(p); 1175 break; 1176 1177 case PT_VM_TIMESTAMP: 1178 td->td_retval[0] = p->p_vmspace->vm_map.timestamp; 1179 break; 1180 1181 case PT_VM_ENTRY: 1182 PROC_UNLOCK(p); 1183#ifdef COMPAT_FREEBSD32 1184 if (wrap32) 1185 error = ptrace_vm_entry32(td, p, addr); 1186 else 1187#endif 1188 error = ptrace_vm_entry(td, p, addr); 1189 PROC_LOCK(p); 1190 break; 1191 1192 default: 1193#ifdef __HAVE_PTRACE_MACHDEP 1194 if (req >= PT_FIRSTMACH) { 1195 PROC_UNLOCK(p); 1196 error = cpu_ptrace(td2, req, addr, data); 1197 PROC_LOCK(p); 1198 } else 1199#endif 1200 /* Unknown request. */ 1201 error = EINVAL; 1202 break; 1203 } 1204 1205out: 1206 /* Drop our hold on this process now that the request has completed. */ 1207 _PRELE(p); 1208fail: 1209 PROC_UNLOCK(p); 1210 if (proctree_locked) 1211 sx_xunlock(&proctree_lock); 1212 return (error); 1213} 1214#undef PROC_READ 1215#undef PROC_WRITE 1216 1217/* 1218 * Stop a process because of a debugging event; 1219 * stay stopped until p->p_step is cleared 1220 * (cleared by PIOCCONT in procfs). 1221 */ 1222void 1223stopevent(struct proc *p, unsigned int event, unsigned int val) 1224{ 1225 1226 PROC_LOCK_ASSERT(p, MA_OWNED); 1227 p->p_step = 1; 1228 do { 1229 p->p_xstat = val; 1230 p->p_xthread = NULL; 1231 p->p_stype = event; /* Which event caused the stop? */ 1232 wakeup(&p->p_stype); /* Wake up any PIOCWAIT'ing procs */ 1233 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0); 1234 } while (p->p_step); 1235} 1236