sys/kern/sys_process.c

   1 /*-
   2  * Copyright (c) 1994, Sean Eric Fagan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Sean Eric Fagan.
  16  * 4. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include "opt_compat.h"
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/lock.h>
  40 #include <sys/mutex.h>
  41 #include <sys/syscallsubr.h>
  42 #include <sys/sysent.h>
  43 #include <sys/sysproto.h>
  44 #include <sys/priv.h>
  45 #include <sys/proc.h>
  46 #include <sys/procctl.h>
  47 #include <sys/vnode.h>
  48 #include <sys/ptrace.h>
  49 #include <sys/sx.h>
  50 #include <sys/malloc.h>
  51 #include <sys/signalvar.h>
  52
  53 #include <machine/reg.h>
  54
  55 #include <security/audit/audit.h>
  56
  57 #include <vm/vm.h>
  58 #include <vm/pmap.h>
  59 #include <vm/vm_extern.h>
  60 #include <vm/vm_map.h>
  61 #include <vm/vm_kern.h>
  62 #include <vm/vm_object.h>
  63 #include <vm/vm_page.h>
  64 #include <vm/vm_pager.h>
  65 #include <vm/vm_param.h>
  66
  67 #ifdef COMPAT_FREEBSD32
  68 #include <sys/procfs.h>
  69 #include <compat/freebsd32/freebsd32_signal.h>
  70
  71 struct ptrace_io_desc32 {
  72         int             piod_op;
  73         uint32_t        piod_offs;
  74         uint32_t        piod_addr;
  75         uint32_t        piod_len;
  76 };
  77
  78 struct ptrace_vm_entry32 {
  79         int             pve_entry;
  80         int             pve_timestamp;
  81         uint32_t        pve_start;
  82         uint32_t        pve_end;
  83         uint32_t        pve_offset;
  84         u_int           pve_prot;
  85         u_int           pve_pathlen;
  86         int32_t         pve_fileid;
  87         u_int           pve_fsid;
  88         uint32_t        pve_path;
  89 };
  90
  91 struct ptrace_lwpinfo32 {
  92         lwpid_t pl_lwpid;       /* LWP described. */
  93         int     pl_event;       /* Event that stopped the LWP. */
  94         int     pl_flags;       /* LWP flags. */
  95         sigset_t        pl_sigmask;     /* LWP signal mask */
  96         sigset_t        pl_siglist;     /* LWP pending signal */
  97         struct siginfo32 pl_siginfo;    /* siginfo for signal */
  98         char    pl_tdname[MAXCOMLEN + 1];       /* LWP name. */
  99         int     pl_child_pid;           /* New child pid */
 100 };
 101
 102 #endif
 103
 104 /*
 105  * Functions implemented using PROC_ACTION():
 106  *
 107  * proc_read_regs(proc, regs)
 108  *      Get the current user-visible register set from the process
 109  *      and copy it into the regs structure (<machine/reg.h>).
 110  *      The process is stopped at the time read_regs is called.
 111  *
 112  * proc_write_regs(proc, regs)
 113  *      Update the current register set from the passed in regs
 114  *      structure.  Take care to avoid clobbering special CPU
 115  *      registers or privileged bits in the PSL.
 116  *      Depending on the architecture this may have fix-up work to do,
 117  *      especially if the IAR or PCW are modified.
 118  *      The process is stopped at the time write_regs is called.
 119  *
 120  * proc_read_fpregs, proc_write_fpregs
 121  *      deal with the floating point register set, otherwise as above.
 122  *
 123  * proc_read_dbregs, proc_write_dbregs
 124  *      deal with the processor debug register set, otherwise as above.
 125  *
 126  * proc_sstep(proc)
 127  *      Arrange for the process to trap after executing a single instruction.
 128  */
 129
 130 #define PROC_ACTION(action) do {                                        \
 131         int error;                                                      \
 132                                                                         \
 133         PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);                        \
 134         if ((td->td_proc->p_flag & P_INMEM) == 0)                       \
 135                 error = EIO;                                            \
 136         else                                                            \
 137                 error = (action);                                       \
 138         return (error);                                                 \
 139 } while(0)
 140
 141 int
 142 proc_read_regs(struct thread *td, struct reg *regs)
 143 {
 144
 145         PROC_ACTION(fill_regs(td, regs));
 146 }
 147
 148 int
 149 proc_write_regs(struct thread *td, struct reg *regs)
 150 {
 151
 152         PROC_ACTION(set_regs(td, regs));
 153 }
 154
 155 int
 156 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
 157 {
 158
 159         PROC_ACTION(fill_dbregs(td, dbregs));
 160 }
 161
 162 int
 163 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
 164 {
 165
 166         PROC_ACTION(set_dbregs(td, dbregs));
 167 }
 168
 169 /*
 170  * Ptrace doesn't support fpregs at all, and there are no security holes
 171  * or translations for fpregs, so we can just copy them.
 172  */
 173 int
 174 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
 175 {
 176
 177         PROC_ACTION(fill_fpregs(td, fpregs));
 178 }
 179
 180 int
 181 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
 182 {
 183
 184         PROC_ACTION(set_fpregs(td, fpregs));
 185 }
 186
 187 #ifdef COMPAT_FREEBSD32
 188 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
 189 int
 190 proc_read_regs32(struct thread *td, struct reg32 *regs32)
 191 {
 192
 193         PROC_ACTION(fill_regs32(td, regs32));
 194 }
 195
 196 int
 197 proc_write_regs32(struct thread *td, struct reg32 *regs32)
 198 {
 199
 200         PROC_ACTION(set_regs32(td, regs32));
 201 }
 202
 203 int
 204 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 205 {
 206
 207         PROC_ACTION(fill_dbregs32(td, dbregs32));
 208 }
 209
 210 int
 211 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
 212 {
 213
 214         PROC_ACTION(set_dbregs32(td, dbregs32));
 215 }
 216
 217 int
 218 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 219 {
 220
 221         PROC_ACTION(fill_fpregs32(td, fpregs32));
 222 }
 223
 224 int
 225 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
 226 {
 227
 228         PROC_ACTION(set_fpregs32(td, fpregs32));
 229 }
 230 #endif
 231
 232 int
 233 proc_sstep(struct thread *td)
 234 {
 235
 236         PROC_ACTION(ptrace_single_step(td));
 237 }
 238
 239 int
 240 proc_rwmem(struct proc *p, struct uio *uio)
 241 {
 242         vm_map_t map;
 243         vm_offset_t pageno;             /* page number */
 244         vm_prot_t reqprot;
 245         int error, fault_flags, page_offset, writing;
 246
 247         /*
 248          * Assert that someone has locked this vmspace.  (Should be
 249          * curthread but we can't assert that.)  This keeps the process
 250          * from exiting out from under us until this operation completes.
 251          */
 252         KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__,
 253             p, p->p_pid));
 254
 255         /*
 256          * The map we want...
 257          */
 258         map = &p->p_vmspace->vm_map;
 259
 260         /*
 261          * If we are writing, then we request vm_fault() to create a private
 262          * copy of each page.  Since these copies will not be writeable by the
 263          * process, we must explicity request that they be dirtied.
 264          */
 265         writing = uio->uio_rw == UIO_WRITE;
 266         reqprot = writing ? VM_PROT_COPY | VM_PROT_READ : VM_PROT_READ;
 267         fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL;
 268
 269         /*
 270          * Only map in one page at a time.  We don't have to, but it
 271          * makes things easier.  This way is trivial - right?
 272          */
 273         do {
 274                 vm_offset_t uva;
 275                 u_int len;
 276                 vm_page_t m;
 277
 278                 uva = (vm_offset_t)uio->uio_offset;
 279
 280                 /*
 281                  * Get the page number of this segment.
 282                  */
 283                 pageno = trunc_page(uva);
 284                 page_offset = uva - pageno;
 285
 286                 /*
 287                  * How many bytes to copy
 288                  */
 289                 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
 290
 291                 /*
 292                  * Fault and hold the page on behalf of the process.
 293                  */
 294                 error = vm_fault_hold(map, pageno, reqprot, fault_flags, &m);
 295                 if (error != KERN_SUCCESS) {
 296                         if (error == KERN_RESOURCE_SHORTAGE)
 297                                 error = ENOMEM;
 298                         else
 299                                 error = EFAULT;
 300                         break;
 301                 }
 302
 303                 /*
 304                  * Now do the i/o move.
 305                  */
 306                 error = uiomove_fromphys(&m, page_offset, len, uio);
 307
 308                 /* Make the I-cache coherent for breakpoints. */
 309                 if (writing && error == 0) {
 310                         vm_map_lock_read(map);
 311                         if (vm_map_check_protection(map, pageno, pageno +
 312                             PAGE_SIZE, VM_PROT_EXECUTE))
 313                                 vm_sync_icache(map, uva, len);
 314                         vm_map_unlock_read(map);
 315                 }
 316
 317                 /*
 318                  * Release the page.
 319                  */
 320                 vm_page_lock(m);
 321                 vm_page_unhold(m);
 322                 vm_page_unlock(m);
 323
 324         } while (error == 0 && uio->uio_resid > 0);
 325
 326         return (error);
 327 }
 328
 329 static int
 330 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
 331 {
 332         struct vattr vattr;
 333         vm_map_t map;
 334         vm_map_entry_t entry;
 335         vm_object_t obj, tobj, lobj;
 336         struct vmspace *vm;
 337         struct vnode *vp;
 338         char *freepath, *fullpath;
 339         u_int pathlen;
 340         int error, index, vfslocked;
 341
 342         error = 0;
 343         obj = NULL;
 344
 345         vm = vmspace_acquire_ref(p);
 346         map = &vm->vm_map;
 347         vm_map_lock_read(map);
 348
 349         do {
 350                 entry = map->header.next;
 351                 index = 0;
 352                 while (index < pve->pve_entry && entry != &map->header) {
 353                         entry = entry->next;
 354                         index++;
 355                 }
 356                 if (index != pve->pve_entry) {
 357                         error = EINVAL;
 358                         break;
 359                 }
 360                 while (entry != &map->header &&
 361                     (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
 362                         entry = entry->next;
 363                         index++;
 364                 }
 365                 if (entry == &map->header) {
 366                         error = ENOENT;
 367                         break;
 368                 }
 369
 370                 /* We got an entry. */
 371                 pve->pve_entry = index + 1;
 372                 pve->pve_timestamp = map->timestamp;
 373                 pve->pve_start = entry->start;
 374                 pve->pve_end = entry->end - 1;
 375                 pve->pve_offset = entry->offset;
 376                 pve->pve_prot = entry->protection;
 377
 378                 /* Backing object's path needed? */
 379                 if (pve->pve_pathlen == 0)
 380                         break;
 381
 382                 pathlen = pve->pve_pathlen;
 383                 pve->pve_pathlen = 0;
 384
 385                 obj = entry->object.vm_object;
 386                 if (obj != NULL)
 387                         VM_OBJECT_LOCK(obj);
 388         } while (0);
 389
 390         vm_map_unlock_read(map);
 391         vmspace_free(vm);
 392
 393         pve->pve_fsid = VNOVAL;
 394         pve->pve_fileid = VNOVAL;
 395
 396         if (error == 0 && obj != NULL) {
 397                 lobj = obj;
 398                 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
 399                         if (tobj != obj)
 400                                 VM_OBJECT_LOCK(tobj);
 401                         if (lobj != obj)
 402                                 VM_OBJECT_UNLOCK(lobj);
 403                         lobj = tobj;
 404                         pve->pve_offset += tobj->backing_object_offset;
 405                 }
 406                 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL;
 407                 if (vp != NULL)
 408                         vref(vp);
 409                 if (lobj != obj)
 410                         VM_OBJECT_UNLOCK(lobj);
 411                 VM_OBJECT_UNLOCK(obj);
 412
 413                 if (vp != NULL) {
 414                         freepath = NULL;
 415                         fullpath = NULL;
 416                         vn_fullpath(td, vp, &fullpath, &freepath);
 417                         vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 418                         vn_lock(vp, LK_SHARED | LK_RETRY);
 419                         if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
 420                                 pve->pve_fileid = vattr.va_fileid;
 421                                 pve->pve_fsid = vattr.va_fsid;
 422                         }
 423                         vput(vp);
 424                         VFS_UNLOCK_GIANT(vfslocked);
 425
 426                         if (fullpath != NULL) {
 427                                 pve->pve_pathlen = strlen(fullpath) + 1;
 428                                 if (pve->pve_pathlen <= pathlen) {
 429                                         error = copyout(fullpath, pve->pve_path,
 430                                             pve->pve_pathlen);
 431                                 } else
 432                                         error = ENAMETOOLONG;
 433                         }
 434                         if (freepath != NULL)
 435                                 free(freepath, M_TEMP);
 436                 }
 437         }
 438
 439         return (error);
 440 }
 441
 442 #ifdef COMPAT_FREEBSD32
 443 static int
 444 ptrace_vm_entry32(struct thread *td, struct proc *p,
 445     struct ptrace_vm_entry32 *pve32)
 446 {
 447         struct ptrace_vm_entry pve;
 448         int error;
 449
 450         pve.pve_entry = pve32->pve_entry;
 451         pve.pve_pathlen = pve32->pve_pathlen;
 452         pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
 453
 454         error = ptrace_vm_entry(td, p, &pve);
 455         if (error == 0) {
 456                 pve32->pve_entry = pve.pve_entry;
 457                 pve32->pve_timestamp = pve.pve_timestamp;
 458                 pve32->pve_start = pve.pve_start;
 459                 pve32->pve_end = pve.pve_end;
 460                 pve32->pve_offset = pve.pve_offset;
 461                 pve32->pve_prot = pve.pve_prot;
 462                 pve32->pve_fileid = pve.pve_fileid;
 463                 pve32->pve_fsid = pve.pve_fsid;
 464         }
 465
 466         pve32->pve_pathlen = pve.pve_pathlen;
 467         return (error);
 468 }
 469
 470 static void
 471 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl,
 472     struct ptrace_lwpinfo32 *pl32)
 473 {
 474
 475         pl32->pl_lwpid = pl->pl_lwpid;
 476         pl32->pl_event = pl->pl_event;
 477         pl32->pl_flags = pl->pl_flags;
 478         pl32->pl_sigmask = pl->pl_sigmask;
 479         pl32->pl_siglist = pl->pl_siglist;
 480         siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo);
 481         strcpy(pl32->pl_tdname, pl->pl_tdname);
 482         pl32->pl_child_pid = pl->pl_child_pid;
 483 }
 484 #endif /* COMPAT_FREEBSD32 */
 485
 486 /*
 487  * Process debugging system call.
 488  */
 489 #ifndef _SYS_SYSPROTO_H_
 490 struct ptrace_args {
 491         int     req;
 492         pid_t   pid;
 493         caddr_t addr;
 494         int     data;
 495 };
 496 #endif
 497
 498 #ifdef COMPAT_FREEBSD32
 499 /*
 500  * This CPP subterfuge is to try and reduce the number of ifdefs in
 501  * the body of the code.
 502  *   COPYIN(uap->addr, &r.reg, sizeof r.reg);
 503  * becomes either:
 504  *   copyin(uap->addr, &r.reg, sizeof r.reg);
 505  * or
 506  *   copyin(uap->addr, &r.reg32, sizeof r.reg32);
 507  * .. except this is done at runtime.
 508  */
 509 #define COPYIN(u, k, s)         wrap32 ? \
 510         copyin(u, k ## 32, s ## 32) : \
 511         copyin(u, k, s)
 512 #define COPYOUT(k, u, s)        wrap32 ? \
 513         copyout(k ## 32, u, s ## 32) : \
 514         copyout(k, u, s)
 515 #else
 516 #define COPYIN(u, k, s)         copyin(u, k, s)
 517 #define COPYOUT(k, u, s)        copyout(k, u, s)
 518 #endif
 519 int
 520 sys_ptrace(struct thread *td, struct ptrace_args *uap)
 521 {
 522         /*
 523          * XXX this obfuscation is to reduce stack usage, but the register
 524          * structs may be too large to put on the stack anyway.
 525          */
 526         union {
 527                 struct ptrace_io_desc piod;
 528                 struct ptrace_lwpinfo pl;
 529                 struct ptrace_vm_entry pve;
 530                 struct dbreg dbreg;
 531                 struct fpreg fpreg;
 532                 struct reg reg;
 533 #ifdef COMPAT_FREEBSD32
 534                 struct dbreg32 dbreg32;
 535                 struct fpreg32 fpreg32;
 536                 struct reg32 reg32;
 537                 struct ptrace_io_desc32 piod32;
 538                 struct ptrace_lwpinfo32 pl32;
 539                 struct ptrace_vm_entry32 pve32;
 540 #endif
 541         } r;
 542         void *addr;
 543         int error = 0;
 544 #ifdef COMPAT_FREEBSD32
 545         int wrap32 = 0;
 546
 547         if (SV_CURPROC_FLAG(SV_ILP32))
 548                 wrap32 = 1;
 549 #endif
 550         AUDIT_ARG_PID(uap->pid);
 551         AUDIT_ARG_CMD(uap->req);
 552         AUDIT_ARG_VALUE(uap->data);
 553         addr = &r;
 554         switch (uap->req) {
 555         case PT_GETREGS:
 556         case PT_GETFPREGS:
 557         case PT_GETDBREGS:
 558         case PT_LWPINFO:
 559                 break;
 560         case PT_SETREGS:
 561                 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
 562                 break;
 563         case PT_SETFPREGS:
 564                 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
 565                 break;
 566         case PT_SETDBREGS:
 567                 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
 568                 break;
 569         case PT_IO:
 570                 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
 571                 break;
 572         case PT_VM_ENTRY:
 573                 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
 574                 break;
 575         default:
 576                 addr = uap->addr;
 577                 break;
 578         }
 579         if (error)
 580                 return (error);
 581
 582         error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
 583         if (error)
 584                 return (error);
 585
 586         switch (uap->req) {
 587         case PT_VM_ENTRY:
 588                 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
 589                 break;
 590         case PT_IO:
 591                 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
 592                 break;
 593         case PT_GETREGS:
 594                 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
 595                 break;
 596         case PT_GETFPREGS:
 597                 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
 598                 break;
 599         case PT_GETDBREGS:
 600                 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
 601                 break;
 602         case PT_LWPINFO:
 603                 error = copyout(&r.pl, uap->addr, uap->data);
 604                 break;
 605         }
 606
 607         return (error);
 608 }
 609 #undef COPYIN
 610 #undef COPYOUT
 611
 612 #ifdef COMPAT_FREEBSD32
 613 /*
 614  *   PROC_READ(regs, td2, addr);
 615  * becomes either:
 616  *   proc_read_regs(td2, addr);
 617  * or
 618  *   proc_read_regs32(td2, addr);
 619  * .. except this is done at runtime.  There is an additional
 620  * complication in that PROC_WRITE disallows 32 bit consumers
 621  * from writing to 64 bit address space targets.
 622  */
 623 #define PROC_READ(w, t, a)      wrap32 ? \
 624         proc_read_ ## w ## 32(t, a) : \
 625         proc_read_ ## w (t, a)
 626 #define PROC_WRITE(w, t, a)     wrap32 ? \
 627         (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
 628         proc_write_ ## w (t, a)
 629 #else
 630 #define PROC_READ(w, t, a)      proc_read_ ## w (t, a)
 631 #define PROC_WRITE(w, t, a)     proc_write_ ## w (t, a)
 632 #endif
 633
 634 int
 635 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 636 {
 637         struct iovec iov;
 638         struct uio uio;
 639         struct proc *curp, *p, *pp;
 640         struct thread *td2 = NULL;
 641         struct ptrace_io_desc *piod = NULL;
 642         struct ptrace_lwpinfo *pl;
 643         int error, write, tmp, num;
 644         int proctree_locked = 0;
 645         lwpid_t tid = 0, *buf;
 646 #ifdef COMPAT_FREEBSD32
 647         int wrap32 = 0, safe = 0;
 648         struct ptrace_io_desc32 *piod32 = NULL;
 649         struct ptrace_lwpinfo32 *pl32 = NULL;
 650         struct ptrace_lwpinfo plr;
 651 #endif
 652
 653         curp = td->td_proc;
 654
 655         /* Lock proctree before locking the process. */
 656         switch (req) {
 657         case PT_TRACE_ME:
 658         case PT_ATTACH:
 659         case PT_STEP:
 660         case PT_CONTINUE:
 661         case PT_TO_SCE:
 662         case PT_TO_SCX:
 663         case PT_SYSCALL:
 664         case PT_FOLLOW_FORK:
 665         case PT_DETACH:
 666                 sx_xlock(&proctree_lock);
 667                 proctree_locked = 1;
 668                 break;
 669         default:
 670                 break;
 671         }
 672
 673         write = 0;
 674         if (req == PT_TRACE_ME) {
 675                 p = td->td_proc;
 676                 PROC_LOCK(p);
 677         } else {
 678                 if (pid <= PID_MAX) {
 679                         if ((p = pfind(pid)) == NULL) {
 680                                 if (proctree_locked)
 681                                         sx_xunlock(&proctree_lock);
 682                                 return (ESRCH);
 683                         }
 684                 } else {
 685                         td2 = tdfind(pid, -1);
 686                         if (td2 == NULL) {
 687                                 if (proctree_locked)
 688                                         sx_xunlock(&proctree_lock);
 689                                 return (ESRCH);
 690                         }
 691                         p = td2->td_proc;
 692                         tid = pid;
 693                         pid = p->p_pid;
 694                 }
 695         }
 696         AUDIT_ARG_PROCESS(p);
 697
 698         if ((p->p_flag & P_WEXIT) != 0) {
 699                 error = ESRCH;
 700                 goto fail;
 701         }
 702         if ((error = p_cansee(td, p)) != 0)
 703                 goto fail;
 704
 705         if ((error = p_candebug(td, p)) != 0)
 706                 goto fail;
 707
 708         /*
 709          * System processes can't be debugged.
 710          */
 711         if ((p->p_flag & P_SYSTEM) != 0) {
 712                 error = EINVAL;
 713                 goto fail;
 714         }
 715
 716         if (tid == 0) {
 717                 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
 718                         KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
 719                         td2 = p->p_xthread;
 720                 } else {
 721                         td2 = FIRST_THREAD_IN_PROC(p);
 722                 }
 723                 tid = td2->td_tid;
 724         }
 725
 726 #ifdef COMPAT_FREEBSD32
 727         /*
 728          * Test if we're a 32 bit client and what the target is.
 729          * Set the wrap controls accordingly.
 730          */
 731         if (SV_CURPROC_FLAG(SV_ILP32)) {
 732                 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
 733                         safe = 1;
 734                 wrap32 = 1;
 735         }
 736 #endif
 737         /*
 738          * Permissions check
 739          */
 740         switch (req) {
 741         case PT_TRACE_ME:
 742                 /* Always legal. */
 743                 break;
 744
 745         case PT_ATTACH:
 746                 /* Self */
 747                 if (p->p_pid == td->td_proc->p_pid) {
 748                         error = EINVAL;
 749                         goto fail;
 750                 }
 751
 752                 /* Already traced */
 753                 if (p->p_flag & P_TRACED) {
 754                         error = EBUSY;
 755                         goto fail;
 756                 }
 757
 758                 /* Can't trace an ancestor if you're being traced. */
 759                 if (curp->p_flag & P_TRACED) {
 760                         for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
 761                                 if (pp == p) {
 762                                         error = EINVAL;
 763                                         goto fail;
 764                                 }
 765                         }
 766                 }
 767
 768
 769                 /* OK */
 770                 break;
 771
 772         case PT_CLEARSTEP:
 773                 /* Allow thread to clear single step for itself */
 774                 if (td->td_tid == tid)
 775                         break;
 776
 777                 /* FALLTHROUGH */
 778         default:
 779                 /* not being traced... */
 780                 if ((p->p_flag & P_TRACED) == 0) {
 781                         error = EPERM;
 782                         goto fail;
 783                 }
 784
 785                 /* not being traced by YOU */
 786                 if (p->p_pptr != td->td_proc) {
 787                         error = EBUSY;
 788                         goto fail;
 789                 }
 790
 791                 /* not currently stopped */
 792                 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 ||
 793                     p->p_suspcount != p->p_numthreads  ||
 794                     (p->p_flag & P_WAITED) == 0) {
 795                         error = EBUSY;
 796                         goto fail;
 797                 }
 798
 799                 if ((p->p_flag & P_STOPPED_TRACE) == 0) {
 800                         static int count = 0;
 801                         if (count++ == 0)
 802                                 printf("P_STOPPED_TRACE not set.\n");
 803                 }
 804
 805                 /* OK */
 806                 break;
 807         }
 808
 809         /* Keep this process around until we finish this request. */
 810         _PHOLD(p);
 811
 812 #ifdef FIX_SSTEP
 813         /*
 814          * Single step fixup ala procfs
 815          */
 816         FIX_SSTEP(td2);
 817 #endif
 818
 819         /*
 820          * Actually do the requests
 821          */
 822
 823         td->td_retval[0] = 0;
 824
 825         switch (req) {
 826         case PT_TRACE_ME:
 827                 /* set my trace flag and "owner" so it can read/write me */
 828                 p->p_flag |= P_TRACED;
 829                 if (p->p_flag & P_PPWAIT)
 830                         p->p_flag |= P_PPTRACE;
 831                 p->p_oppid = p->p_pptr->p_pid;
 832                 break;
 833
 834         case PT_ATTACH:
 835                 /* security check done above */
 836                 /*
 837                  * It would be nice if the tracing relationship was separate
 838                  * from the parent relationship but that would require
 839                  * another set of links in the proc struct or for "wait"
 840                  * to scan the entire proc table.  To make life easier,
 841                  * we just re-parent the process we're trying to trace.
 842                  * The old parent is remembered so we can put things back
 843                  * on a "detach".
 844                  */
 845                 p->p_flag |= P_TRACED;
 846                 p->p_oppid = p->p_pptr->p_pid;
 847                 if (p->p_pptr != td->td_proc) {
 848                         proc_reparent(p, td->td_proc);
 849                 }
 850                 data = SIGSTOP;
 851                 goto sendsig;   /* in PT_CONTINUE below */
 852
 853         case PT_CLEARSTEP:
 854                 error = ptrace_clear_single_step(td2);
 855                 break;
 856
 857         case PT_SETSTEP:
 858                 error = ptrace_single_step(td2);
 859                 break;
 860
 861         case PT_SUSPEND:
 862                 td2->td_dbgflags |= TDB_SUSPEND;
 863                 thread_lock(td2);
 864                 td2->td_flags |= TDF_NEEDSUSPCHK;
 865                 thread_unlock(td2);
 866                 break;
 867
 868         case PT_RESUME:
 869                 td2->td_dbgflags &= ~TDB_SUSPEND;
 870                 break;
 871
 872         case PT_FOLLOW_FORK:
 873                 if (data)
 874                         p->p_flag |= P_FOLLOWFORK;
 875                 else
 876                         p->p_flag &= ~P_FOLLOWFORK;
 877                 break;
 878
 879         case PT_STEP:
 880         case PT_CONTINUE:
 881         case PT_TO_SCE:
 882         case PT_TO_SCX:
 883         case PT_SYSCALL:
 884         case PT_DETACH:
 885                 /* Zero means do not send any signal */
 886                 if (data < 0 || data > _SIG_MAXSIG) {
 887                         error = EINVAL;
 888                         break;
 889                 }
 890
 891                 switch (req) {
 892                 case PT_STEP:
 893                         error = ptrace_single_step(td2);
 894                         if (error)
 895                                 goto out;
 896                         break;
 897                 case PT_CONTINUE:
 898                 case PT_TO_SCE:
 899                 case PT_TO_SCX:
 900                 case PT_SYSCALL:
 901                         if (addr != (void *)1) {
 902                                 error = ptrace_set_pc(td2,
 903                                     (u_long)(uintfptr_t)addr);
 904                                 if (error)
 905                                         goto out;
 906                         }
 907                         switch (req) {
 908                         case PT_TO_SCE:
 909                                 p->p_stops |= S_PT_SCE;
 910                                 break;
 911                         case PT_TO_SCX:
 912                                 p->p_stops |= S_PT_SCX;
 913                                 break;
 914                         case PT_SYSCALL:
 915                                 p->p_stops |= S_PT_SCE | S_PT_SCX;
 916                                 break;
 917                         }
 918                         break;
 919                 case PT_DETACH:
 920                         /* reset process parent */
 921                         if (p->p_oppid != p->p_pptr->p_pid) {
 922                                 struct proc *pp;
 923
 924                                 PROC_LOCK(p->p_pptr);
 925                                 sigqueue_take(p->p_ksi);
 926                                 PROC_UNLOCK(p->p_pptr);
 927
 928                                 PROC_UNLOCK(p);
 929                                 pp = pfind(p->p_oppid);
 930                                 if (pp == NULL)
 931                                         pp = initproc;
 932                                 else
 933                                         PROC_UNLOCK(pp);
 934                                 PROC_LOCK(p);
 935                                 proc_reparent(p, pp);
 936                                 if (pp == initproc)
 937                                         p->p_sigparent = SIGCHLD;
 938                         }
 939                         p->p_oppid = 0;
 940                         p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK);
 941
 942                         /* should we send SIGCHLD? */
 943                         /* childproc_continued(p); */
 944                         break;
 945                 }
 946
 947         sendsig:
 948                 if (proctree_locked) {
 949                         sx_xunlock(&proctree_lock);
 950                         proctree_locked = 0;
 951                 }
 952                 p->p_xstat = data;
 953                 p->p_xthread = NULL;
 954                 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) {
 955                         /* deliver or queue signal */
 956                         td2->td_dbgflags &= ~TDB_XSIG;
 957                         td2->td_xsig = data;
 958
 959                         if (req == PT_DETACH) {
 960                                 struct thread *td3;
 961                                 FOREACH_THREAD_IN_PROC(p, td3) {
 962                                         td3->td_dbgflags &= ~TDB_SUSPEND;
 963                                 }
 964                         }
 965                         /*
 966                          * unsuspend all threads, to not let a thread run,
 967                          * you should use PT_SUSPEND to suspend it before
 968                          * continuing process.
 969                          */
 970                         PROC_SLOCK(p);
 971                         p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED);
 972                         thread_unsuspend(p);
 973                         PROC_SUNLOCK(p);
 974                 } else {
 975                         if (data)
 976                                 kern_psignal(p, data);
 977                 }
 978                 break;
 979
 980         case PT_WRITE_I:
 981         case PT_WRITE_D:
 982                 td2->td_dbgflags |= TDB_USERWR;
 983                 write = 1;
 984                 /* FALLTHROUGH */
 985         case PT_READ_I:
 986         case PT_READ_D:
 987                 PROC_UNLOCK(p);
 988                 tmp = 0;
 989                 /* write = 0 set above */
 990                 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
 991                 iov.iov_len = sizeof(int);
 992                 uio.uio_iov = &iov;
 993                 uio.uio_iovcnt = 1;
 994                 uio.uio_offset = (off_t)(uintptr_t)addr;
 995                 uio.uio_resid = sizeof(int);
 996                 uio.uio_segflg = UIO_SYSSPACE;  /* i.e.: the uap */
 997                 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
 998                 uio.uio_td = td;
 999                 error = proc_rwmem(p, &uio);
1000                 if (uio.uio_resid != 0) {
1001                         /*
1002                          * XXX proc_rwmem() doesn't currently return ENOSPC,
1003                          * so I think write() can bogusly return 0.
1004                          * XXX what happens for short writes?  We don't want
1005                          * to write partial data.
1006                          * XXX proc_rwmem() returns EPERM for other invalid
1007                          * addresses.  Convert this to EINVAL.  Does this
1008                          * clobber returns of EPERM for other reasons?
1009                          */
1010                         if (error == 0 || error == ENOSPC || error == EPERM)
1011                                 error = EINVAL; /* EOF */
1012                 }
1013                 if (!write)
1014                         td->td_retval[0] = tmp;
1015                 PROC_LOCK(p);
1016                 break;
1017
1018         case PT_IO:
1019 #ifdef COMPAT_FREEBSD32
1020                 if (wrap32) {
1021                         piod32 = addr;
1022                         iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
1023                         iov.iov_len = piod32->piod_len;
1024                         uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
1025                         uio.uio_resid = piod32->piod_len;
1026                 } else
1027 #endif
1028                 {
1029                         piod = addr;
1030                         iov.iov_base = piod->piod_addr;
1031                         iov.iov_len = piod->piod_len;
1032                         uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
1033                         uio.uio_resid = piod->piod_len;
1034                 }
1035                 uio.uio_iov = &iov;
1036                 uio.uio_iovcnt = 1;
1037                 uio.uio_segflg = UIO_USERSPACE;
1038                 uio.uio_td = td;
1039 #ifdef COMPAT_FREEBSD32
1040                 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
1041 #else
1042                 tmp = piod->piod_op;
1043 #endif
1044                 switch (tmp) {
1045                 case PIOD_READ_D:
1046                 case PIOD_READ_I:
1047                         uio.uio_rw = UIO_READ;
1048                         break;
1049                 case PIOD_WRITE_D:
1050                 case PIOD_WRITE_I:
1051                         td2->td_dbgflags |= TDB_USERWR;
1052                         uio.uio_rw = UIO_WRITE;
1053                         break;
1054                 default:
1055                         error = EINVAL;
1056                         goto out;
1057                 }
1058                 PROC_UNLOCK(p);
1059                 error = proc_rwmem(p, &uio);
1060 #ifdef COMPAT_FREEBSD32
1061                 if (wrap32)
1062                         piod32->piod_len -= uio.uio_resid;
1063                 else
1064 #endif
1065                         piod->piod_len -= uio.uio_resid;
1066                 PROC_LOCK(p);
1067                 break;
1068
1069         case PT_KILL:
1070                 data = SIGKILL;
1071                 goto sendsig;   /* in PT_CONTINUE above */
1072
1073         case PT_SETREGS:
1074                 td2->td_dbgflags |= TDB_USERWR;
1075                 error = PROC_WRITE(regs, td2, addr);
1076                 break;
1077
1078         case PT_GETREGS:
1079                 error = PROC_READ(regs, td2, addr);
1080                 break;
1081
1082         case PT_SETFPREGS:
1083                 td2->td_dbgflags |= TDB_USERWR;
1084                 error = PROC_WRITE(fpregs, td2, addr);
1085                 break;
1086
1087         case PT_GETFPREGS:
1088                 error = PROC_READ(fpregs, td2, addr);
1089                 break;
1090
1091         case PT_SETDBREGS:
1092                 td2->td_dbgflags |= TDB_USERWR;
1093                 error = PROC_WRITE(dbregs, td2, addr);
1094                 break;
1095
1096         case PT_GETDBREGS:
1097                 error = PROC_READ(dbregs, td2, addr);
1098                 break;
1099
1100         case PT_LWPINFO:
1101                 if (data <= 0 ||
1102 #ifdef COMPAT_FREEBSD32
1103                     (!wrap32 && data > sizeof(*pl)) ||
1104                     (wrap32 && data > sizeof(*pl32))) {
1105 #else
1106                     data > sizeof(*pl)) {
1107 #endif
1108                         error = EINVAL;
1109                         break;
1110                 }
1111 #ifdef COMPAT_FREEBSD32
1112                 if (wrap32) {
1113                         pl = &plr;
1114                         pl32 = addr;
1115                 } else
1116 #endif
1117                 pl = addr;
1118                 pl->pl_lwpid = td2->td_tid;
1119                 pl->pl_event = PL_EVENT_NONE;
1120                 pl->pl_flags = 0;
1121                 if (td2->td_dbgflags & TDB_XSIG) {
1122                         pl->pl_event = PL_EVENT_SIGNAL;
1123                         if (td2->td_dbgksi.ksi_signo != 0 &&
1124 #ifdef COMPAT_FREEBSD32
1125                             ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo,
1126                             pl_siginfo) + sizeof(pl->pl_siginfo)) ||
1127                             (wrap32 && data >= offsetof(struct ptrace_lwpinfo32,
1128                             pl_siginfo) + sizeof(struct siginfo32)))
1129 #else
1130                             data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
1131                             + sizeof(pl->pl_siginfo)
1132 #endif
1133                         ){
1134                                 pl->pl_flags |= PL_FLAG_SI;
1135                                 pl->pl_siginfo = td2->td_dbgksi.ksi_info;
1136                         }
1137                 }
1138                 if ((pl->pl_flags & PL_FLAG_SI) == 0)
1139                         bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo));
1140                 if (td2->td_dbgflags & TDB_SCE)
1141                         pl->pl_flags |= PL_FLAG_SCE;
1142                 else if (td2->td_dbgflags & TDB_SCX)
1143                         pl->pl_flags |= PL_FLAG_SCX;
1144                 if (td2->td_dbgflags & TDB_EXEC)
1145                         pl->pl_flags |= PL_FLAG_EXEC;
1146                 if (td2->td_dbgflags & TDB_FORK) {
1147                         pl->pl_flags |= PL_FLAG_FORKED;
1148                         pl->pl_child_pid = td2->td_dbg_forked;
1149                 }
1150                 if (td2->td_dbgflags & TDB_CHILD)
1151                         pl->pl_flags |= PL_FLAG_CHILD;
1152                 pl->pl_sigmask = td2->td_sigmask;
1153                 pl->pl_siglist = td2->td_siglist;
1154                 strcpy(pl->pl_tdname, td2->td_name);
1155 #ifdef COMPAT_FREEBSD32
1156                 if (wrap32)
1157                         ptrace_lwpinfo_to32(pl, pl32);
1158 #endif
1159                 break;
1160
1161         case PT_GETNUMLWPS:
1162                 td->td_retval[0] = p->p_numthreads;
1163                 break;
1164
1165         case PT_GETLWPLIST:
1166                 if (data <= 0) {
1167                         error = EINVAL;
1168                         break;
1169                 }
1170                 num = imin(p->p_numthreads, data);
1171                 PROC_UNLOCK(p);
1172                 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
1173                 tmp = 0;
1174                 PROC_LOCK(p);
1175                 FOREACH_THREAD_IN_PROC(p, td2) {
1176                         if (tmp >= num)
1177                                 break;
1178                         buf[tmp++] = td2->td_tid;
1179                 }
1180                 PROC_UNLOCK(p);
1181                 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
1182                 free(buf, M_TEMP);
1183                 if (!error)
1184                         td->td_retval[0] = tmp;
1185                 PROC_LOCK(p);
1186                 break;
1187
1188         case PT_VM_TIMESTAMP:
1189                 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
1190                 break;
1191
1192         case PT_VM_ENTRY:
1193                 PROC_UNLOCK(p);
1194 #ifdef COMPAT_FREEBSD32
1195                 if (wrap32)
1196                         error = ptrace_vm_entry32(td, p, addr);
1197                 else
1198 #endif
1199                 error = ptrace_vm_entry(td, p, addr);
1200                 PROC_LOCK(p);
1201                 break;
1202
1203         default:
1204 #ifdef __HAVE_PTRACE_MACHDEP
1205                 if (req >= PT_FIRSTMACH) {
1206                         PROC_UNLOCK(p);
1207                         error = cpu_ptrace(td2, req, addr, data);
1208                         PROC_LOCK(p);
1209                 } else
1210 #endif
1211                         /* Unknown request. */
1212                         error = EINVAL;
1213                 break;
1214         }
1215
1216 out:
1217         /* Drop our hold on this process now that the request has completed. */
1218         _PRELE(p);
1219 fail:
1220         PROC_UNLOCK(p);
1221         if (proctree_locked)
1222                 sx_xunlock(&proctree_lock);
1223         return (error);
1224 }
1225 #undef PROC_READ
1226 #undef PROC_WRITE
1227
1228 /*
1229  * Stop a process because of a debugging event;
1230  * stay stopped until p->p_step is cleared
1231  * (cleared by PIOCCONT in procfs).
1232  */
1233 void
1234 stopevent(struct proc *p, unsigned int event, unsigned int val)
1235 {
1236
1237         PROC_LOCK_ASSERT(p, MA_OWNED);
1238         p->p_step = 1;
1239         do {
1240                 p->p_xstat = val;
1241                 p->p_xthread = NULL;
1242                 p->p_stype = event;     /* Which event caused the stop? */
1243                 wakeup(&p->p_stype);    /* Wake up any PIOCWAIT'ing procs */
1244                 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
1245         } while (p->p_step);
1246 }
1247
1248 static int
1249 protect_setchild(struct thread *td, struct proc *p, int flags)
1250 {
1251
1252         PROC_LOCK_ASSERT(p, MA_OWNED);
1253         if (p->p_flag & P_SYSTEM || p_cansee(td, p) != 0)
1254                 return (0);
1255         if (flags & PPROT_SET) {
1256                 p->p_flag |= P_PROTECTED;
1257                 if (flags & PPROT_INHERIT)
1258                         p->p_flag2 |= P2_INHERIT_PROTECTED;
1259         } else {
1260                 p->p_flag &= ~P_PROTECTED;
1261                 p->p_flag2 &= ~P2_INHERIT_PROTECTED;
1262         }
1263         return (1);
1264 }
1265
1266 static int
1267 protect_setchildren(struct thread *td, struct proc *top, int flags)
1268 {
1269         struct proc *p;
1270         int ret;
1271
1272         p = top;
1273         ret = 0;
1274         sx_assert(&proctree_lock, SX_LOCKED);
1275         for (;;) {
1276                 ret |= protect_setchild(td, p, flags);
1277                 PROC_UNLOCK(p);
1278                 /*
1279                  * If this process has children, descend to them next,
1280                  * otherwise do any siblings, and if done with this level,
1281                  * follow back up the tree (but not past top).
1282                  */
1283                 if (!LIST_EMPTY(&p->p_children))
1284                         p = LIST_FIRST(&p->p_children);
1285                 else for (;;) {
1286                         if (p == top) {
1287                                 PROC_LOCK(p);
1288                                 return (ret);
1289                         }
1290                         if (LIST_NEXT(p, p_sibling)) {
1291                                 p = LIST_NEXT(p, p_sibling);
1292                                 break;
1293                         }
1294                         p = p->p_pptr;
1295                 }
1296                 PROC_LOCK(p);
1297         }
1298 }
1299
1300 static int
1301 protect_set(struct thread *td, struct proc *p, int flags)
1302 {
1303         int error, ret;
1304
1305         switch (PPROT_OP(flags)) {
1306         case PPROT_SET:
1307         case PPROT_CLEAR:
1308                 break;
1309         default:
1310                 return (EINVAL);
1311         }
1312
1313         if ((PPROT_FLAGS(flags) & ~(PPROT_DESCEND | PPROT_INHERIT)) != 0)
1314                 return (EINVAL);
1315
1316         error = priv_check(td, PRIV_VM_MADV_PROTECT);
1317         if (error)
1318                 return (error);
1319
1320         if (flags & PPROT_DESCEND)
1321                 ret = protect_setchildren(td, p, flags);
1322         else
1323                 ret = protect_setchild(td, p, flags);
1324         if (ret == 0)
1325                 return (EPERM);
1326         return (0);
1327 }
1328
1329 #ifndef _SYS_SYSPROTO_H_
1330 struct procctl_args {
1331         idtype_t idtype;
1332         id_t    id;
1333         int     com;
1334         void    *data;
1335 };
1336 #endif
1337 /* ARGSUSED */
1338 int
1339 sys_procctl(struct thread *td, struct procctl_args *uap)
1340 {
1341         int error, flags;
1342         void *data;
1343
1344         switch (uap->com) {
1345         case PROC_SPROTECT:
1346                 error = copyin(uap->data, &flags, sizeof(flags));
1347                 if (error)
1348                         return (error);
1349                 data = &flags;
1350                 break;
1351         default:
1352                 return (EINVAL);
1353         }
1354
1355         return (kern_procctl(td, uap->idtype, uap->id, uap->com, data));
1356 }
1357
1358 static int
1359 kern_procctl_single(struct thread *td, struct proc *p, int com, void *data)
1360 {
1361
1362         PROC_LOCK_ASSERT(p, MA_OWNED);
1363         switch (com) {
1364         case PROC_SPROTECT:
1365                 return (protect_set(td, p, *(int *)data));
1366         default:
1367                 return (EINVAL);
1368         }
1369 }
1370
1371 int
1372 kern_procctl(struct thread *td, idtype_t idtype, id_t id, int com, void *data)
1373 {
1374         struct pgrp *pg;
1375         struct proc *p;
1376         int error, first_error, ok;
1377
1378         sx_slock(&proctree_lock);
1379         switch (idtype) {
1380         case P_PID:
1381                 p = pfind(id);
1382                 if (p == NULL) {
1383                         error = ESRCH;
1384                         break;
1385                 }
1386                 if (p->p_state == PRS_NEW)
1387                         error = ESRCH;
1388                 else
1389                         error = p_cansee(td, p);
1390                 if (error == 0)
1391                         error = kern_procctl_single(td, p, com, data);
1392                 PROC_UNLOCK(p);
1393                 break;
1394         case P_PGID:
1395                 /*
1396                  * Attempt to apply the operation to all members of the
1397                  * group.  Ignore processes in the group that can't be
1398                  * seen.  Ignore errors so long as at least one process is
1399                  * able to complete the request successfully.
1400                  */
1401                 pg = pgfind(id);
1402                 if (pg == NULL) {
1403                         error = ESRCH;
1404                         break;
1405                 }
1406                 PGRP_UNLOCK(pg);
1407                 ok = 0;
1408                 first_error = 0;
1409                 LIST_FOREACH(p, &pg->pg_members, p_pglist) {
1410                         PROC_LOCK(p);
1411                         if (p->p_state == PRS_NEW || p_cansee(td, p) != 0) {
1412                                 PROC_UNLOCK(p);
1413                                 continue;
1414                         }
1415                         error = kern_procctl_single(td, p, com, data);
1416                         PROC_UNLOCK(p);
1417                         if (error == 0)
1418                                 ok = 1;
1419                         else if (first_error == 0)
1420                                 first_error = error;
1421                 }
1422                 if (ok)
1423                         error = 0;
1424                 else if (first_error != 0)
1425                         error = first_error;
1426                 else
1427                         /*
1428                          * Was not able to see any processes in the
1429                          * process group.
1430                          */
1431                         error = ESRCH;
1432                 break;
1433         default:
1434                 error = EINVAL;
1435                 break;
1436         }
1437         sx_sunlock(&proctree_lock);
1438         return (error);
1439 }