sys/vfs/procfs/procfs_dbregs.c

   1 /*-
   2  * Copyright (c) 1999 Brian Scott Dean, brdean@unx.sas.com.
   3  *                    All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Jan-Simon Pendry under the following copyrights and conditions:
   7  *
   8  * Copyright (c) 1993 Jan-Simon Pendry
   9  * Copyright (c) 1993
  10  *      The Regents of the University of California.  All rights reserved.
  11  *
  12  * This code is derived from software contributed to Berkeley by
  13  * Jan-Simon Pendry.
  14  *
  15  * Redistribution and use in source and binary forms, with or without
  16  * modification, are permitted provided that the following conditions
  17  * are met:
  18  * 1. Redistributions of source code must retain the above copyright
  19  *    notice, this list of conditions and the following disclaimer.
  20  * 2. Redistributions in binary form must reproduce the above copyright
  21  *    notice, this list of conditions and the following disclaimer in the
  22  *    documentation and/or other materials provided with the distribution.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  *
  39  * $FreeBSD: src/sys/miscfs/procfs/procfs_dbregs.c,v 1.4.2.3 2002/01/22 17:22:59 nectar Exp $
  40  * $DragonFly: src/sys/vfs/procfs/procfs_dbregs.c,v 1.10 2007/02/19 01:14:24 corecode Exp $
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/proc.h>
  45 #include <sys/priv.h>
  46 #include <sys/vnode.h>
  47 #include <sys/reg.h>
  48 #include <vfs/procfs/procfs.h>
  49 #include <vm/vm.h>
  50
  51 int
  52 procfs_dodbregs(struct proc *curp, struct lwp *lp, struct pfsnode *pfs,
  53                 struct uio *uio)
  54 {
  55         struct proc *p = lp->lwp_proc;
  56         int error;
  57         struct dbreg r;
  58
  59         /* Can't trace a process that's currently exec'ing. */
  60         if ((p->p_flags & P_INEXEC) != 0)
  61                 return EAGAIN;
  62         if (!CHECKIO(curp, p) || p_trespass(curp->p_ucred, p->p_ucred))
  63                 return (EPERM);
  64         LWPHOLD(lp);
  65         error = procfs_read_dbregs(lp, &r);
  66         if (error == 0)
  67                 error = uiomove_frombuf(&r, sizeof(r), uio);
  68         if (error == 0 && uio->uio_rw == UIO_WRITE) {
  69                 if (lp->lwp_stat != LSSTOP)
  70                         error = EBUSY;
  71                 else
  72                         error = procfs_write_dbregs(lp, &r);
  73         }
  74         LWPRELE(lp);
  75         uio->uio_offset = 0;
  76
  77         return (error);
  78 }
  79
  80 int
  81 procfs_validdbregs(struct lwp *lp)
  82 {
  83         return ((lp->lwp_proc->p_flags & P_SYSTEM) == 0);
  84 }