The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/kern/sys_process.c

Version: -  FREEBSD  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-2  -  FREEBSD-11-1  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-4  -  FREEBSD-10-3  -  FREEBSD-10-2  -  FREEBSD-10-1  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-3  -  FREEBSD-9-2  -  FREEBSD-9-1  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-4  -  FREEBSD-8-3  -  FREEBSD-8-2  -  FREEBSD-8-1  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-4  -  FREEBSD-7-3  -  FREEBSD-7-2  -  FREEBSD-7-1  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-4  -  FREEBSD-6-3  -  FREEBSD-6-2  -  FREEBSD-6-1  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-5  -  FREEBSD-5-4  -  FREEBSD-5-3  -  FREEBSD-5-2  -  FREEBSD-5-1  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    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: releng/8.3/sys/kern/sys_process.c 219144 2011-03-01 20:44:14Z dchagin $");
   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/proc.h>
   45 #include <sys/vnode.h>
   46 #include <sys/ptrace.h>
   47 #include <sys/sx.h>
   48 #include <sys/malloc.h>
   49 #include <sys/signalvar.h>
   50 
   51 #include <machine/reg.h>
   52 
   53 #include <security/audit/audit.h>
   54 
   55 #include <vm/vm.h>
   56 #include <vm/pmap.h>
   57 #include <vm/vm_extern.h>
   58 #include <vm/vm_map.h>
   59 #include <vm/vm_kern.h>
   60 #include <vm/vm_object.h>
   61 #include <vm/vm_page.h>
   62 #include <vm/vm_param.h>
   63 
   64 #ifdef COMPAT_FREEBSD32
   65 #include <sys/procfs.h>
   66 #include <compat/freebsd32/freebsd32_signal.h>
   67 
   68 struct ptrace_io_desc32 {
   69         int             piod_op;
   70         u_int32_t       piod_offs;
   71         u_int32_t       piod_addr;
   72         u_int32_t       piod_len;
   73 };
   74 
   75 struct ptrace_vm_entry32 {
   76         int             pve_entry;
   77         int             pve_timestamp;
   78         uint32_t        pve_start;
   79         uint32_t        pve_end;
   80         uint32_t        pve_offset;
   81         u_int           pve_prot;
   82         u_int           pve_pathlen;
   83         int32_t         pve_fileid;
   84         u_int           pve_fsid;
   85         uint32_t        pve_path;
   86 };
   87 
   88 struct ptrace_lwpinfo32 {
   89         lwpid_t pl_lwpid;       /* LWP described. */
   90         int     pl_event;       /* Event that stopped the LWP. */
   91         int     pl_flags;       /* LWP flags. */
   92         sigset_t        pl_sigmask;     /* LWP signal mask */
   93         sigset_t        pl_siglist;     /* LWP pending signal */
   94         struct siginfo32 pl_siginfo;    /* siginfo for signal */
   95         char    pl_tdname[MAXCOMLEN + 1];       /* LWP name. */
   96         int     pl_child_pid;           /* New child pid */
   97 };
   98 
   99 #endif
  100 
  101 /*
  102  * Functions implemented using PROC_ACTION():
  103  *
  104  * proc_read_regs(proc, regs)
  105  *      Get the current user-visible register set from the process
  106  *      and copy it into the regs structure (<machine/reg.h>).
  107  *      The process is stopped at the time read_regs is called.
  108  *
  109  * proc_write_regs(proc, regs)
  110  *      Update the current register set from the passed in regs
  111  *      structure.  Take care to avoid clobbering special CPU
  112  *      registers or privileged bits in the PSL.
  113  *      Depending on the architecture this may have fix-up work to do,
  114  *      especially if the IAR or PCW are modified.
  115  *      The process is stopped at the time write_regs is called.
  116  *
  117  * proc_read_fpregs, proc_write_fpregs
  118  *      deal with the floating point register set, otherwise as above.
  119  *
  120  * proc_read_dbregs, proc_write_dbregs
  121  *      deal with the processor debug register set, otherwise as above.
  122  *
  123  * proc_sstep(proc)
  124  *      Arrange for the process to trap after executing a single instruction.
  125  */
  126 
  127 #define PROC_ACTION(action) do {                                        \
  128         int error;                                                      \
  129                                                                         \
  130         PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);                        \
  131         if ((td->td_proc->p_flag & P_INMEM) == 0)                       \
  132                 error = EIO;                                            \
  133         else                                                            \
  134                 error = (action);                                       \
  135         return (error);                                                 \
  136 } while(0)
  137 
  138 int
  139 proc_read_regs(struct thread *td, struct reg *regs)
  140 {
  141 
  142         PROC_ACTION(fill_regs(td, regs));
  143 }
  144 
  145 int
  146 proc_write_regs(struct thread *td, struct reg *regs)
  147 {
  148 
  149         PROC_ACTION(set_regs(td, regs));
  150 }
  151 
  152 int
  153 proc_read_dbregs(struct thread *td, struct dbreg *dbregs)
  154 {
  155 
  156         PROC_ACTION(fill_dbregs(td, dbregs));
  157 }
  158 
  159 int
  160 proc_write_dbregs(struct thread *td, struct dbreg *dbregs)
  161 {
  162 
  163         PROC_ACTION(set_dbregs(td, dbregs));
  164 }
  165 
  166 /*
  167  * Ptrace doesn't support fpregs at all, and there are no security holes
  168  * or translations for fpregs, so we can just copy them.
  169  */
  170 int
  171 proc_read_fpregs(struct thread *td, struct fpreg *fpregs)
  172 {
  173 
  174         PROC_ACTION(fill_fpregs(td, fpregs));
  175 }
  176 
  177 int
  178 proc_write_fpregs(struct thread *td, struct fpreg *fpregs)
  179 {
  180 
  181         PROC_ACTION(set_fpregs(td, fpregs));
  182 }
  183 
  184 #ifdef COMPAT_FREEBSD32
  185 /* For 32 bit binaries, we need to expose the 32 bit regs layouts. */
  186 int
  187 proc_read_regs32(struct thread *td, struct reg32 *regs32)
  188 {
  189 
  190         PROC_ACTION(fill_regs32(td, regs32));
  191 }
  192 
  193 int
  194 proc_write_regs32(struct thread *td, struct reg32 *regs32)
  195 {
  196 
  197         PROC_ACTION(set_regs32(td, regs32));
  198 }
  199 
  200 int
  201 proc_read_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
  202 {
  203 
  204         PROC_ACTION(fill_dbregs32(td, dbregs32));
  205 }
  206 
  207 int
  208 proc_write_dbregs32(struct thread *td, struct dbreg32 *dbregs32)
  209 {
  210 
  211         PROC_ACTION(set_dbregs32(td, dbregs32));
  212 }
  213 
  214 int
  215 proc_read_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
  216 {
  217 
  218         PROC_ACTION(fill_fpregs32(td, fpregs32));
  219 }
  220 
  221 int
  222 proc_write_fpregs32(struct thread *td, struct fpreg32 *fpregs32)
  223 {
  224 
  225         PROC_ACTION(set_fpregs32(td, fpregs32));
  226 }
  227 #endif
  228 
  229 int
  230 proc_sstep(struct thread *td)
  231 {
  232 
  233         PROC_ACTION(ptrace_single_step(td));
  234 }
  235 
  236 int
  237 proc_rwmem(struct proc *p, struct uio *uio)
  238 {
  239         vm_map_t map;
  240         vm_object_t backing_object, object = NULL;
  241         vm_offset_t pageno = 0;         /* page number */
  242         vm_prot_t reqprot;
  243         int error, fault_flags, writing;
  244 
  245         /*
  246          * Assert that someone has locked this vmspace.  (Should be
  247          * curthread but we can't assert that.)  This keeps the process
  248          * from exiting out from under us until this operation completes.
  249          */
  250         KASSERT(p->p_lock >= 1, ("%s: process %p (pid %d) not held", __func__,
  251             p, p->p_pid));
  252 
  253         /*
  254          * The map we want...
  255          */
  256         map = &p->p_vmspace->vm_map;
  257 
  258         writing = uio->uio_rw == UIO_WRITE;
  259         reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) :
  260             VM_PROT_READ;
  261         fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; 
  262 
  263         /*
  264          * Only map in one page at a time.  We don't have to, but it
  265          * makes things easier.  This way is trivial - right?
  266          */
  267         do {
  268                 vm_map_t tmap;
  269                 vm_offset_t uva;
  270                 int page_offset;                /* offset into page */
  271                 vm_map_entry_t out_entry;
  272                 vm_prot_t out_prot;
  273                 boolean_t wired;
  274                 vm_pindex_t pindex;
  275                 u_int len;
  276                 vm_page_t m;
  277 
  278                 object = NULL;
  279 
  280                 uva = (vm_offset_t)uio->uio_offset;
  281 
  282                 /*
  283                  * Get the page number of this segment.
  284                  */
  285                 pageno = trunc_page(uva);
  286                 page_offset = uva - pageno;
  287 
  288                 /*
  289                  * How many bytes to copy
  290                  */
  291                 len = min(PAGE_SIZE - page_offset, uio->uio_resid);
  292 
  293                 /*
  294                  * Fault the page on behalf of the process
  295                  */
  296                 error = vm_fault(map, pageno, reqprot, fault_flags);
  297                 if (error) {
  298                         if (error == KERN_RESOURCE_SHORTAGE)
  299                                 error = ENOMEM;
  300                         else
  301                                 error = EFAULT;
  302                         break;
  303                 }
  304 
  305                 /*
  306                  * Now we need to get the page.  out_entry, out_prot, wired,
  307                  * and single_use aren't used.  One would think the vm code
  308                  * would be a *bit* nicer...  We use tmap because
  309                  * vm_map_lookup() can change the map argument.
  310                  */
  311                 tmap = map;
  312                 error = vm_map_lookup(&tmap, pageno, reqprot, &out_entry,
  313                     &object, &pindex, &out_prot, &wired);
  314                 if (error) {
  315                         error = EFAULT;
  316                         break;
  317                 }
  318                 VM_OBJECT_LOCK(object);
  319                 while ((m = vm_page_lookup(object, pindex)) == NULL &&
  320                     !writing &&
  321                     (backing_object = object->backing_object) != NULL) {
  322                         /*
  323                          * Allow fallback to backing objects if we are reading.
  324                          */
  325                         VM_OBJECT_LOCK(backing_object);
  326                         pindex += OFF_TO_IDX(object->backing_object_offset);
  327                         VM_OBJECT_UNLOCK(object);
  328                         object = backing_object;
  329                 }
  330                 VM_OBJECT_UNLOCK(object);
  331                 if (m == NULL) {
  332                         vm_map_lookup_done(tmap, out_entry);
  333                         error = EFAULT;
  334                         break;
  335                 }
  336 
  337                 /*
  338                  * Hold the page in memory.
  339                  */
  340                 vm_page_lock_queues();
  341                 vm_page_hold(m);
  342                 vm_page_unlock_queues();
  343 
  344                 /*
  345                  * We're done with tmap now.
  346                  */
  347                 vm_map_lookup_done(tmap, out_entry);
  348 
  349                 /*
  350                  * Now do the i/o move.
  351                  */
  352                 error = uiomove_fromphys(&m, page_offset, len, uio);
  353 
  354                 /* Make the I-cache coherent for breakpoints. */
  355                 if (!error && writing && (out_prot & VM_PROT_EXECUTE))
  356                         vm_sync_icache(map, uva, len);
  357 
  358                 /*
  359                  * Release the page.
  360                  */
  361                 vm_page_lock_queues();
  362                 vm_page_unhold(m);
  363                 vm_page_unlock_queues();
  364 
  365         } while (error == 0 && uio->uio_resid > 0);
  366 
  367         return (error);
  368 }
  369 
  370 static int
  371 ptrace_vm_entry(struct thread *td, struct proc *p, struct ptrace_vm_entry *pve)
  372 {
  373         struct vattr vattr;
  374         vm_map_t map;
  375         vm_map_entry_t entry;
  376         vm_object_t obj, tobj, lobj;
  377         struct vmspace *vm;
  378         struct vnode *vp;
  379         char *freepath, *fullpath;
  380         u_int pathlen;
  381         int error, index, vfslocked;
  382 
  383         error = 0;
  384         obj = NULL;
  385 
  386         vm = vmspace_acquire_ref(p);
  387         map = &vm->vm_map;
  388         vm_map_lock_read(map);
  389 
  390         do {
  391                 entry = map->header.next;
  392                 index = 0;
  393                 while (index < pve->pve_entry && entry != &map->header) {
  394                         entry = entry->next;
  395                         index++;
  396                 }
  397                 if (index != pve->pve_entry) {
  398                         error = EINVAL;
  399                         break;
  400                 }
  401                 while (entry != &map->header &&
  402                     (entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
  403                         entry = entry->next;
  404                         index++;
  405                 }
  406                 if (entry == &map->header) {
  407                         error = ENOENT;
  408                         break;
  409                 }
  410 
  411                 /* We got an entry. */
  412                 pve->pve_entry = index + 1;
  413                 pve->pve_timestamp = map->timestamp;
  414                 pve->pve_start = entry->start;
  415                 pve->pve_end = entry->end - 1;
  416                 pve->pve_offset = entry->offset;
  417                 pve->pve_prot = entry->protection;
  418 
  419                 /* Backing object's path needed? */
  420                 if (pve->pve_pathlen == 0)
  421                         break;
  422 
  423                 pathlen = pve->pve_pathlen;
  424                 pve->pve_pathlen = 0;
  425 
  426                 obj = entry->object.vm_object;
  427                 if (obj != NULL)
  428                         VM_OBJECT_LOCK(obj);
  429         } while (0);
  430 
  431         vm_map_unlock_read(map);
  432         vmspace_free(vm);
  433 
  434         pve->pve_fsid = VNOVAL;
  435         pve->pve_fileid = VNOVAL;
  436 
  437         if (error == 0 && obj != NULL) {
  438                 lobj = obj;
  439                 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) {
  440                         if (tobj != obj)
  441                                 VM_OBJECT_LOCK(tobj);
  442                         if (lobj != obj)
  443                                 VM_OBJECT_UNLOCK(lobj);
  444                         lobj = tobj;
  445                         pve->pve_offset += tobj->backing_object_offset;
  446                 }
  447                 vp = (lobj->type == OBJT_VNODE) ? lobj->handle : NULL;
  448                 if (vp != NULL)
  449                         vref(vp);
  450                 if (lobj != obj)
  451                         VM_OBJECT_UNLOCK(lobj);
  452                 VM_OBJECT_UNLOCK(obj);
  453 
  454                 if (vp != NULL) {
  455                         freepath = NULL;
  456                         fullpath = NULL;
  457                         vn_fullpath(td, vp, &fullpath, &freepath);
  458                         vfslocked = VFS_LOCK_GIANT(vp->v_mount);
  459                         vn_lock(vp, LK_SHARED | LK_RETRY);
  460                         if (VOP_GETATTR(vp, &vattr, td->td_ucred) == 0) {
  461                                 pve->pve_fileid = vattr.va_fileid;
  462                                 pve->pve_fsid = vattr.va_fsid;
  463                         }
  464                         vput(vp);
  465                         VFS_UNLOCK_GIANT(vfslocked);
  466 
  467                         if (fullpath != NULL) {
  468                                 pve->pve_pathlen = strlen(fullpath) + 1;
  469                                 if (pve->pve_pathlen <= pathlen) {
  470                                         error = copyout(fullpath, pve->pve_path,
  471                                             pve->pve_pathlen);
  472                                 } else
  473                                         error = ENAMETOOLONG;
  474                         }
  475                         if (freepath != NULL)
  476                                 free(freepath, M_TEMP);
  477                 }
  478         }
  479 
  480         return (error);
  481 }
  482 
  483 #ifdef COMPAT_FREEBSD32
  484 static int      
  485 ptrace_vm_entry32(struct thread *td, struct proc *p,
  486     struct ptrace_vm_entry32 *pve32)
  487 {
  488         struct ptrace_vm_entry pve;
  489         int error;
  490 
  491         pve.pve_entry = pve32->pve_entry;
  492         pve.pve_pathlen = pve32->pve_pathlen;
  493         pve.pve_path = (void *)(uintptr_t)pve32->pve_path;
  494 
  495         error = ptrace_vm_entry(td, p, &pve);
  496         if (error == 0) {
  497                 pve32->pve_entry = pve.pve_entry;
  498                 pve32->pve_timestamp = pve.pve_timestamp;
  499                 pve32->pve_start = pve.pve_start;
  500                 pve32->pve_end = pve.pve_end;
  501                 pve32->pve_offset = pve.pve_offset;
  502                 pve32->pve_prot = pve.pve_prot;
  503                 pve32->pve_fileid = pve.pve_fileid;
  504                 pve32->pve_fsid = pve.pve_fsid;
  505         }
  506 
  507         pve32->pve_pathlen = pve.pve_pathlen;
  508         return (error);
  509 }
  510 
  511 static void
  512 ptrace_lwpinfo_to32(const struct ptrace_lwpinfo *pl,
  513     struct ptrace_lwpinfo32 *pl32)
  514 {
  515 
  516         pl32->pl_lwpid = pl->pl_lwpid;
  517         pl32->pl_event = pl->pl_event;
  518         pl32->pl_flags = pl->pl_flags;
  519         pl32->pl_sigmask = pl->pl_sigmask;
  520         pl32->pl_siglist = pl->pl_siglist;
  521         siginfo_to_siginfo32(&pl->pl_siginfo, &pl32->pl_siginfo);
  522         strcpy(pl32->pl_tdname, pl->pl_tdname);
  523         pl32->pl_child_pid = pl->pl_child_pid;
  524 }
  525 #endif /* COMPAT_FREEBSD32 */
  526 
  527 /*
  528  * Process debugging system call.
  529  */
  530 #ifndef _SYS_SYSPROTO_H_
  531 struct ptrace_args {
  532         int     req;
  533         pid_t   pid;
  534         caddr_t addr;
  535         int     data;
  536 };
  537 #endif
  538 
  539 #ifdef COMPAT_FREEBSD32
  540 /*
  541  * This CPP subterfuge is to try and reduce the number of ifdefs in
  542  * the body of the code.
  543  *   COPYIN(uap->addr, &r.reg, sizeof r.reg);
  544  * becomes either:
  545  *   copyin(uap->addr, &r.reg, sizeof r.reg);
  546  * or
  547  *   copyin(uap->addr, &r.reg32, sizeof r.reg32);
  548  * .. except this is done at runtime.
  549  */
  550 #define COPYIN(u, k, s)         wrap32 ? \
  551         copyin(u, k ## 32, s ## 32) : \
  552         copyin(u, k, s)
  553 #define COPYOUT(k, u, s)        wrap32 ? \
  554         copyout(k ## 32, u, s ## 32) : \
  555         copyout(k, u, s)
  556 #else
  557 #define COPYIN(u, k, s)         copyin(u, k, s)
  558 #define COPYOUT(k, u, s)        copyout(k, u, s)
  559 #endif
  560 int
  561 ptrace(struct thread *td, struct ptrace_args *uap)
  562 {
  563         /*
  564          * XXX this obfuscation is to reduce stack usage, but the register
  565          * structs may be too large to put on the stack anyway.
  566          */
  567         union {
  568                 struct ptrace_io_desc piod;
  569                 struct ptrace_lwpinfo pl;
  570                 struct ptrace_vm_entry pve;
  571                 struct dbreg dbreg;
  572                 struct fpreg fpreg;
  573                 struct reg reg;
  574 #ifdef COMPAT_FREEBSD32
  575                 struct dbreg32 dbreg32;
  576                 struct fpreg32 fpreg32;
  577                 struct reg32 reg32;
  578                 struct ptrace_io_desc32 piod32;
  579                 struct ptrace_lwpinfo32 pl32;
  580                 struct ptrace_vm_entry32 pve32;
  581 #endif
  582         } r;
  583         void *addr;
  584         int error = 0;
  585 #ifdef COMPAT_FREEBSD32
  586         int wrap32 = 0;
  587 
  588         if (SV_CURPROC_FLAG(SV_ILP32))
  589                 wrap32 = 1;
  590 #endif
  591         AUDIT_ARG_PID(uap->pid);
  592         AUDIT_ARG_CMD(uap->req);
  593         AUDIT_ARG_VALUE(uap->data);
  594         addr = &r;
  595         switch (uap->req) {
  596         case PT_GETREGS:
  597         case PT_GETFPREGS:
  598         case PT_GETDBREGS:
  599         case PT_LWPINFO:
  600                 break;
  601         case PT_SETREGS:
  602                 error = COPYIN(uap->addr, &r.reg, sizeof r.reg);
  603                 break;
  604         case PT_SETFPREGS:
  605                 error = COPYIN(uap->addr, &r.fpreg, sizeof r.fpreg);
  606                 break;
  607         case PT_SETDBREGS:
  608                 error = COPYIN(uap->addr, &r.dbreg, sizeof r.dbreg);
  609                 break;
  610         case PT_IO:
  611                 error = COPYIN(uap->addr, &r.piod, sizeof r.piod);
  612                 break;
  613         case PT_VM_ENTRY:
  614                 error = COPYIN(uap->addr, &r.pve, sizeof r.pve);
  615                 break;
  616         default:
  617                 addr = uap->addr;
  618                 break;
  619         }
  620         if (error)
  621                 return (error);
  622 
  623         error = kern_ptrace(td, uap->req, uap->pid, addr, uap->data);
  624         if (error)
  625                 return (error);
  626 
  627         switch (uap->req) {
  628         case PT_VM_ENTRY:
  629                 error = COPYOUT(&r.pve, uap->addr, sizeof r.pve);
  630                 break;
  631         case PT_IO:
  632                 error = COPYOUT(&r.piod, uap->addr, sizeof r.piod);
  633                 break;
  634         case PT_GETREGS:
  635                 error = COPYOUT(&r.reg, uap->addr, sizeof r.reg);
  636                 break;
  637         case PT_GETFPREGS:
  638                 error = COPYOUT(&r.fpreg, uap->addr, sizeof r.fpreg);
  639                 break;
  640         case PT_GETDBREGS:
  641                 error = COPYOUT(&r.dbreg, uap->addr, sizeof r.dbreg);
  642                 break;
  643         case PT_LWPINFO:
  644                 error = copyout(&r.pl, uap->addr, uap->data);
  645                 break;
  646         }
  647 
  648         return (error);
  649 }
  650 #undef COPYIN
  651 #undef COPYOUT
  652 
  653 #ifdef COMPAT_FREEBSD32
  654 /*
  655  *   PROC_READ(regs, td2, addr);
  656  * becomes either:
  657  *   proc_read_regs(td2, addr);
  658  * or
  659  *   proc_read_regs32(td2, addr);
  660  * .. except this is done at runtime.  There is an additional
  661  * complication in that PROC_WRITE disallows 32 bit consumers
  662  * from writing to 64 bit address space targets.
  663  */
  664 #define PROC_READ(w, t, a)      wrap32 ? \
  665         proc_read_ ## w ## 32(t, a) : \
  666         proc_read_ ## w (t, a)
  667 #define PROC_WRITE(w, t, a)     wrap32 ? \
  668         (safe ? proc_write_ ## w ## 32(t, a) : EINVAL ) : \
  669         proc_write_ ## w (t, a)
  670 #else
  671 #define PROC_READ(w, t, a)      proc_read_ ## w (t, a)
  672 #define PROC_WRITE(w, t, a)     proc_write_ ## w (t, a)
  673 #endif
  674 
  675 int
  676 kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
  677 {
  678         struct iovec iov;
  679         struct uio uio;
  680         struct proc *curp, *p, *pp;
  681         struct thread *td2 = NULL;
  682         struct ptrace_io_desc *piod = NULL;
  683         struct ptrace_lwpinfo *pl;
  684         int error, write, tmp, num;
  685         int proctree_locked = 0;
  686         lwpid_t tid = 0, *buf;
  687 #ifdef COMPAT_FREEBSD32
  688         int wrap32 = 0, safe = 0;
  689         struct ptrace_io_desc32 *piod32 = NULL;
  690         struct ptrace_lwpinfo32 *pl32 = NULL;
  691         struct ptrace_lwpinfo plr;
  692 #endif
  693 
  694         curp = td->td_proc;
  695 
  696         /* Lock proctree before locking the process. */
  697         switch (req) {
  698         case PT_TRACE_ME:
  699         case PT_ATTACH:
  700         case PT_STEP:
  701         case PT_CONTINUE:
  702         case PT_TO_SCE:
  703         case PT_TO_SCX:
  704         case PT_SYSCALL:
  705         case PT_FOLLOW_FORK:
  706         case PT_DETACH:
  707                 sx_xlock(&proctree_lock);
  708                 proctree_locked = 1;
  709                 break;
  710         default:
  711                 break;
  712         }
  713 
  714         write = 0;
  715         if (req == PT_TRACE_ME) {
  716                 p = td->td_proc;
  717                 PROC_LOCK(p);
  718         } else {
  719                 if (pid <= PID_MAX) {
  720                         if ((p = pfind(pid)) == NULL) {
  721                                 if (proctree_locked)
  722                                         sx_xunlock(&proctree_lock);
  723                                 return (ESRCH);
  724                         }
  725                 } else {
  726                         /* this is slow, should be optimized */
  727                         sx_slock(&allproc_lock);
  728                         FOREACH_PROC_IN_SYSTEM(p) {
  729                                 PROC_LOCK(p);
  730                                 FOREACH_THREAD_IN_PROC(p, td2) {
  731                                         if (td2->td_tid == pid)
  732                                                 break;
  733                                 }
  734                                 if (td2 != NULL)
  735                                         break; /* proc lock held */
  736                                 PROC_UNLOCK(p);
  737                         }
  738                         sx_sunlock(&allproc_lock);
  739                         if (p == NULL) {
  740                                 if (proctree_locked)
  741                                         sx_xunlock(&proctree_lock);
  742                                 return (ESRCH);
  743                         }
  744                         tid = pid;
  745                         pid = p->p_pid;
  746                 }
  747         }
  748         AUDIT_ARG_PROCESS(p);
  749 
  750         if ((p->p_flag & P_WEXIT) != 0) {
  751                 error = ESRCH;
  752                 goto fail;
  753         }
  754         if ((error = p_cansee(td, p)) != 0)
  755                 goto fail;
  756 
  757         if ((error = p_candebug(td, p)) != 0)
  758                 goto fail;
  759 
  760         /*
  761          * System processes can't be debugged.
  762          */
  763         if ((p->p_flag & P_SYSTEM) != 0) {
  764                 error = EINVAL;
  765                 goto fail;
  766         }
  767 
  768         if (tid == 0) {
  769                 if ((p->p_flag & P_STOPPED_TRACE) != 0) {
  770                         KASSERT(p->p_xthread != NULL, ("NULL p_xthread"));
  771                         td2 = p->p_xthread;
  772                 } else {
  773                         td2 = FIRST_THREAD_IN_PROC(p);
  774                 }
  775                 tid = td2->td_tid;
  776         }
  777 
  778 #ifdef COMPAT_FREEBSD32
  779         /*
  780          * Test if we're a 32 bit client and what the target is.
  781          * Set the wrap controls accordingly.
  782          */
  783         if (SV_CURPROC_FLAG(SV_ILP32)) {
  784                 if (SV_PROC_FLAG(td2->td_proc, SV_ILP32))
  785                         safe = 1;
  786                 wrap32 = 1;
  787         }
  788 #endif
  789         /*
  790          * Permissions check
  791          */
  792         switch (req) {
  793         case PT_TRACE_ME:
  794                 /* Always legal. */
  795                 break;
  796 
  797         case PT_ATTACH:
  798                 /* Self */
  799                 if (p->p_pid == td->td_proc->p_pid) {
  800                         error = EINVAL;
  801                         goto fail;
  802                 }
  803 
  804                 /* Already traced */
  805                 if (p->p_flag & P_TRACED) {
  806                         error = EBUSY;
  807                         goto fail;
  808                 }
  809 
  810                 /* Can't trace an ancestor if you're being traced. */
  811                 if (curp->p_flag & P_TRACED) {
  812                         for (pp = curp->p_pptr; pp != NULL; pp = pp->p_pptr) {
  813                                 if (pp == p) {
  814                                         error = EINVAL;
  815                                         goto fail;
  816                                 }
  817                         }
  818                 }
  819 
  820 
  821                 /* OK */
  822                 break;
  823 
  824         case PT_CLEARSTEP:
  825                 /* Allow thread to clear single step for itself */
  826                 if (td->td_tid == tid)
  827                         break;
  828 
  829                 /* FALLTHROUGH */
  830         default:
  831                 /* not being traced... */
  832                 if ((p->p_flag & P_TRACED) == 0) {
  833                         error = EPERM;
  834                         goto fail;
  835                 }
  836 
  837                 /* not being traced by YOU */
  838                 if (p->p_pptr != td->td_proc) {
  839                         error = EBUSY;
  840                         goto fail;
  841                 }
  842 
  843                 /* not currently stopped */
  844                 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) == 0 ||
  845                     p->p_suspcount != p->p_numthreads  ||
  846                     (p->p_flag & P_WAITED) == 0) {
  847                         error = EBUSY;
  848                         goto fail;
  849                 }
  850 
  851                 if ((p->p_flag & P_STOPPED_TRACE) == 0) {
  852                         static int count = 0;
  853                         if (count++ == 0)
  854                                 printf("P_STOPPED_TRACE not set.\n");
  855                 }
  856 
  857                 /* OK */
  858                 break;
  859         }
  860 
  861         /* Keep this process around until we finish this request. */
  862         _PHOLD(p);
  863 
  864 #ifdef FIX_SSTEP
  865         /*
  866          * Single step fixup ala procfs
  867          */
  868         FIX_SSTEP(td2);
  869 #endif
  870 
  871         /*
  872          * Actually do the requests
  873          */
  874 
  875         td->td_retval[0] = 0;
  876 
  877         switch (req) {
  878         case PT_TRACE_ME:
  879                 /* set my trace flag and "owner" so it can read/write me */
  880                 p->p_flag |= P_TRACED;
  881                 p->p_oppid = p->p_pptr->p_pid;
  882                 break;
  883 
  884         case PT_ATTACH:
  885                 /* security check done above */
  886                 p->p_flag |= P_TRACED;
  887                 p->p_oppid = p->p_pptr->p_pid;
  888                 if (p->p_pptr != td->td_proc)
  889                         proc_reparent(p, td->td_proc);
  890                 data = SIGSTOP;
  891                 goto sendsig;   /* in PT_CONTINUE below */
  892 
  893         case PT_CLEARSTEP:
  894                 error = ptrace_clear_single_step(td2);
  895                 break;
  896 
  897         case PT_SETSTEP:
  898                 error = ptrace_single_step(td2);
  899                 break;
  900 
  901         case PT_SUSPEND:
  902                 td2->td_dbgflags |= TDB_SUSPEND;
  903                 thread_lock(td2);
  904                 td2->td_flags |= TDF_NEEDSUSPCHK;
  905                 thread_unlock(td2);
  906                 break;
  907 
  908         case PT_RESUME:
  909                 td2->td_dbgflags &= ~TDB_SUSPEND;
  910                 break;
  911 
  912         case PT_FOLLOW_FORK:
  913                 if (data)
  914                         p->p_flag |= P_FOLLOWFORK;
  915                 else
  916                         p->p_flag &= ~P_FOLLOWFORK;
  917                 break;
  918 
  919         case PT_STEP:
  920         case PT_CONTINUE:
  921         case PT_TO_SCE:
  922         case PT_TO_SCX:
  923         case PT_SYSCALL:
  924         case PT_DETACH:
  925                 /* Zero means do not send any signal */
  926                 if (data < 0 || data > _SIG_MAXSIG) {
  927                         error = EINVAL;
  928                         break;
  929                 }
  930 
  931                 switch (req) {
  932                 case PT_STEP:
  933                         error = ptrace_single_step(td2);
  934                         if (error)
  935                                 goto out;
  936                         break;
  937                 case PT_CONTINUE:
  938                 case PT_TO_SCE:
  939                 case PT_TO_SCX:
  940                 case PT_SYSCALL:
  941                         if (addr != (void *)1) {
  942                                 error = ptrace_set_pc(td2,
  943                                     (u_long)(uintfptr_t)addr);
  944                                 if (error)
  945                                         goto out;
  946                         }
  947                         switch (req) {
  948                         case PT_TO_SCE:
  949                                 p->p_stops |= S_PT_SCE;
  950                                 break;
  951                         case PT_TO_SCX:
  952                                 p->p_stops |= S_PT_SCX;
  953                                 break;
  954                         case PT_SYSCALL:
  955                                 p->p_stops |= S_PT_SCE | S_PT_SCX;
  956                                 break;
  957                         }
  958                         break;
  959                 case PT_DETACH:
  960                         /* reset process parent */
  961                         if (p->p_oppid != p->p_pptr->p_pid) {
  962                                 struct proc *pp;
  963 
  964                                 PROC_LOCK(p->p_pptr);
  965                                 sigqueue_take(p->p_ksi);
  966                                 PROC_UNLOCK(p->p_pptr);
  967 
  968                                 PROC_UNLOCK(p);
  969                                 pp = pfind(p->p_oppid);
  970                                 if (pp == NULL)
  971                                         pp = initproc;
  972                                 else
  973                                         PROC_UNLOCK(pp);
  974                                 PROC_LOCK(p);
  975                                 proc_reparent(p, pp);
  976                                 if (pp == initproc)
  977                                         p->p_sigparent = SIGCHLD;
  978                         }
  979                         p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK);
  980                         p->p_oppid = 0;
  981 
  982                         /* should we send SIGCHLD? */
  983                         /* childproc_continued(p); */
  984                         break;
  985                 }
  986 
  987         sendsig:
  988                 if (proctree_locked) {
  989                         sx_xunlock(&proctree_lock);
  990                         proctree_locked = 0;
  991                 }
  992                 p->p_xstat = data;
  993                 p->p_xthread = NULL;
  994                 if ((p->p_flag & (P_STOPPED_SIG | P_STOPPED_TRACE)) != 0) {
  995                         /* deliver or queue signal */
  996                         td2->td_dbgflags &= ~TDB_XSIG;
  997                         td2->td_xsig = data;
  998 
  999                         if (req == PT_DETACH) {
 1000                                 struct thread *td3;
 1001                                 FOREACH_THREAD_IN_PROC(p, td3) {
 1002                                         td3->td_dbgflags &= ~TDB_SUSPEND; 
 1003                                 }
 1004                         }
 1005                         /*
 1006                          * unsuspend all threads, to not let a thread run,
 1007                          * you should use PT_SUSPEND to suspend it before
 1008                          * continuing process.
 1009                          */
 1010                         PROC_SLOCK(p);
 1011                         p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG|P_WAITED);
 1012                         thread_unsuspend(p);
 1013                         PROC_SUNLOCK(p);
 1014                 } else {
 1015                         if (data)
 1016                                 psignal(p, data);
 1017                 }
 1018                 break;
 1019 
 1020         case PT_WRITE_I:
 1021         case PT_WRITE_D:
 1022                 td2->td_dbgflags |= TDB_USERWR;
 1023                 write = 1;
 1024                 /* FALLTHROUGH */
 1025         case PT_READ_I:
 1026         case PT_READ_D:
 1027                 PROC_UNLOCK(p);
 1028                 tmp = 0;
 1029                 /* write = 0 set above */
 1030                 iov.iov_base = write ? (caddr_t)&data : (caddr_t)&tmp;
 1031                 iov.iov_len = sizeof(int);
 1032                 uio.uio_iov = &iov;
 1033                 uio.uio_iovcnt = 1;
 1034                 uio.uio_offset = (off_t)(uintptr_t)addr;
 1035                 uio.uio_resid = sizeof(int);
 1036                 uio.uio_segflg = UIO_SYSSPACE;  /* i.e.: the uap */
 1037                 uio.uio_rw = write ? UIO_WRITE : UIO_READ;
 1038                 uio.uio_td = td;
 1039                 error = proc_rwmem(p, &uio);
 1040                 if (uio.uio_resid != 0) {
 1041                         /*
 1042                          * XXX proc_rwmem() doesn't currently return ENOSPC,
 1043                          * so I think write() can bogusly return 0.
 1044                          * XXX what happens for short writes?  We don't want
 1045                          * to write partial data.
 1046                          * XXX proc_rwmem() returns EPERM for other invalid
 1047                          * addresses.  Convert this to EINVAL.  Does this
 1048                          * clobber returns of EPERM for other reasons?
 1049                          */
 1050                         if (error == 0 || error == ENOSPC || error == EPERM)
 1051                                 error = EINVAL; /* EOF */
 1052                 }
 1053                 if (!write)
 1054                         td->td_retval[0] = tmp;
 1055                 PROC_LOCK(p);
 1056                 break;
 1057 
 1058         case PT_IO:
 1059 #ifdef COMPAT_FREEBSD32
 1060                 if (wrap32) {
 1061                         piod32 = addr;
 1062                         iov.iov_base = (void *)(uintptr_t)piod32->piod_addr;
 1063                         iov.iov_len = piod32->piod_len;
 1064                         uio.uio_offset = (off_t)(uintptr_t)piod32->piod_offs;
 1065                         uio.uio_resid = piod32->piod_len;
 1066                 } else
 1067 #endif
 1068                 {
 1069                         piod = addr;
 1070                         iov.iov_base = piod->piod_addr;
 1071                         iov.iov_len = piod->piod_len;
 1072                         uio.uio_offset = (off_t)(uintptr_t)piod->piod_offs;
 1073                         uio.uio_resid = piod->piod_len;
 1074                 }
 1075                 uio.uio_iov = &iov;
 1076                 uio.uio_iovcnt = 1;
 1077                 uio.uio_segflg = UIO_USERSPACE;
 1078                 uio.uio_td = td;
 1079 #ifdef COMPAT_FREEBSD32
 1080                 tmp = wrap32 ? piod32->piod_op : piod->piod_op;
 1081 #else
 1082                 tmp = piod->piod_op;
 1083 #endif
 1084                 switch (tmp) {
 1085                 case PIOD_READ_D:
 1086                 case PIOD_READ_I:
 1087                         uio.uio_rw = UIO_READ;
 1088                         break;
 1089                 case PIOD_WRITE_D:
 1090                 case PIOD_WRITE_I:
 1091                         td2->td_dbgflags |= TDB_USERWR;
 1092                         uio.uio_rw = UIO_WRITE;
 1093                         break;
 1094                 default:
 1095                         error = EINVAL;
 1096                         goto out;
 1097                 }
 1098                 PROC_UNLOCK(p);
 1099                 error = proc_rwmem(p, &uio);
 1100 #ifdef COMPAT_FREEBSD32
 1101                 if (wrap32)
 1102                         piod32->piod_len -= uio.uio_resid;
 1103                 else
 1104 #endif
 1105                         piod->piod_len -= uio.uio_resid;
 1106                 PROC_LOCK(p);
 1107                 break;
 1108 
 1109         case PT_KILL:
 1110                 data = SIGKILL;
 1111                 goto sendsig;   /* in PT_CONTINUE above */
 1112 
 1113         case PT_SETREGS:
 1114                 td2->td_dbgflags |= TDB_USERWR;
 1115                 error = PROC_WRITE(regs, td2, addr);
 1116                 break;
 1117 
 1118         case PT_GETREGS:
 1119                 error = PROC_READ(regs, td2, addr);
 1120                 break;
 1121 
 1122         case PT_SETFPREGS:
 1123                 td2->td_dbgflags |= TDB_USERWR;
 1124                 error = PROC_WRITE(fpregs, td2, addr);
 1125                 break;
 1126 
 1127         case PT_GETFPREGS:
 1128                 error = PROC_READ(fpregs, td2, addr);
 1129                 break;
 1130 
 1131         case PT_SETDBREGS:
 1132                 td2->td_dbgflags |= TDB_USERWR;
 1133                 error = PROC_WRITE(dbregs, td2, addr);
 1134                 break;
 1135 
 1136         case PT_GETDBREGS:
 1137                 error = PROC_READ(dbregs, td2, addr);
 1138                 break;
 1139 
 1140         case PT_LWPINFO:
 1141                 if (data <= 0 ||
 1142 #ifdef COMPAT_FREEBSD32
 1143                     (!wrap32 && data > sizeof(*pl)) ||
 1144                     (wrap32 && data > sizeof(*pl32))) {
 1145 #else
 1146                     data > sizeof(*pl)) {
 1147 #endif
 1148                         error = EINVAL;
 1149                         break;
 1150                 }
 1151 #ifdef COMPAT_FREEBSD32
 1152                 if (wrap32) {
 1153                         pl = &plr;
 1154                         pl32 = addr;
 1155                 } else
 1156 #endif
 1157                 pl = addr;
 1158                 pl->pl_lwpid = td2->td_tid;
 1159                 pl->pl_flags = 0;
 1160                 if (td2->td_dbgflags & TDB_XSIG) {
 1161                         pl->pl_event = PL_EVENT_SIGNAL;
 1162                         if (td2->td_dbgksi.ksi_signo != 0 &&
 1163 #ifdef COMPAT_FREEBSD32
 1164                             ((!wrap32 && data >= offsetof(struct ptrace_lwpinfo,
 1165                             pl_siginfo) + sizeof(pl->pl_siginfo)) ||
 1166                             (wrap32 && data >= offsetof(struct ptrace_lwpinfo32,
 1167                             pl_siginfo) + sizeof(struct siginfo32)))
 1168 #else
 1169                             data >= offsetof(struct ptrace_lwpinfo, pl_siginfo)
 1170                             + sizeof(pl->pl_siginfo)
 1171 #endif
 1172                         ){
 1173                                 pl->pl_flags |= PL_FLAG_SI;
 1174                                 pl->pl_siginfo = td2->td_dbgksi.ksi_info;
 1175                         }
 1176                 }
 1177                 if ((pl->pl_flags & PL_FLAG_SI) == 0)
 1178                         bzero(&pl->pl_siginfo, sizeof(pl->pl_siginfo));
 1179                 if (td2->td_dbgflags & TDB_SCE)
 1180                         pl->pl_flags |= PL_FLAG_SCE;
 1181                 else if (td2->td_dbgflags & TDB_SCX)
 1182                         pl->pl_flags |= PL_FLAG_SCX;
 1183                 if (td2->td_dbgflags & TDB_EXEC)
 1184                         pl->pl_flags |= PL_FLAG_EXEC;
 1185                 if (td2->td_dbgflags & TDB_FORK) {
 1186                         pl->pl_flags |= PL_FLAG_FORKED;
 1187                         pl->pl_child_pid = td2->td_dbg_forked;
 1188                 }
 1189                 pl->pl_sigmask = td2->td_sigmask;
 1190                 pl->pl_siglist = td2->td_siglist;
 1191                 strcpy(pl->pl_tdname, td2->td_name);
 1192 #ifdef COMPAT_FREEBSD32
 1193                 if (wrap32)
 1194                         ptrace_lwpinfo_to32(pl, pl32);
 1195 #endif
 1196                 break;
 1197 
 1198         case PT_GETNUMLWPS:
 1199                 td->td_retval[0] = p->p_numthreads;
 1200                 break;
 1201 
 1202         case PT_GETLWPLIST:
 1203                 if (data <= 0) {
 1204                         error = EINVAL;
 1205                         break;
 1206                 }
 1207                 num = imin(p->p_numthreads, data);
 1208                 PROC_UNLOCK(p);
 1209                 buf = malloc(num * sizeof(lwpid_t), M_TEMP, M_WAITOK);
 1210                 tmp = 0;
 1211                 PROC_LOCK(p);
 1212                 FOREACH_THREAD_IN_PROC(p, td2) {
 1213                         if (tmp >= num)
 1214                                 break;
 1215                         buf[tmp++] = td2->td_tid;
 1216                 }
 1217                 PROC_UNLOCK(p);
 1218                 error = copyout(buf, addr, tmp * sizeof(lwpid_t));
 1219                 free(buf, M_TEMP);
 1220                 if (!error)
 1221                         td->td_retval[0] = tmp;
 1222                 PROC_LOCK(p);
 1223                 break;
 1224 
 1225         case PT_VM_TIMESTAMP:
 1226                 td->td_retval[0] = p->p_vmspace->vm_map.timestamp;
 1227                 break;
 1228 
 1229         case PT_VM_ENTRY:
 1230                 PROC_UNLOCK(p);
 1231 #ifdef COMPAT_FREEBSD32
 1232                 if (wrap32)
 1233                         error = ptrace_vm_entry32(td, p, addr);
 1234                 else
 1235 #endif
 1236                 error = ptrace_vm_entry(td, p, addr);
 1237                 PROC_LOCK(p);
 1238                 break;
 1239 
 1240         default:
 1241 #ifdef __HAVE_PTRACE_MACHDEP
 1242                 if (req >= PT_FIRSTMACH) {
 1243                         PROC_UNLOCK(p);
 1244                         error = cpu_ptrace(td2, req, addr, data);
 1245                         PROC_LOCK(p);
 1246                 } else
 1247 #endif
 1248                         /* Unknown request. */
 1249                         error = EINVAL;
 1250                 break;
 1251         }
 1252 
 1253 out:
 1254         /* Drop our hold on this process now that the request has completed. */
 1255         _PRELE(p);
 1256 fail:
 1257         PROC_UNLOCK(p);
 1258         if (proctree_locked)
 1259                 sx_xunlock(&proctree_lock);
 1260         return (error);
 1261 }
 1262 #undef PROC_READ
 1263 #undef PROC_WRITE
 1264 
 1265 /*
 1266  * Stop a process because of a debugging event;
 1267  * stay stopped until p->p_step is cleared
 1268  * (cleared by PIOCCONT in procfs).
 1269  */
 1270 void
 1271 stopevent(struct proc *p, unsigned int event, unsigned int val)
 1272 {
 1273 
 1274         PROC_LOCK_ASSERT(p, MA_OWNED);
 1275         p->p_step = 1;
 1276         do {
 1277                 p->p_xstat = val;
 1278                 p->p_xthread = NULL;
 1279                 p->p_stype = event;     /* Which event caused the stop? */
 1280                 wakeup(&p->p_stype);    /* Wake up any PIOCWAIT'ing procs */
 1281                 msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
 1282         } while (p->p_step);
 1283 }

Cache object: 07b3c15e8774e862fa1050603f3e4745


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.