This commit was manufactured by cvs2svn to create tag 'FreeBSD-release/1.0'.

[unix-history] / sys / kern / sys_process.c

diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index f4c9c06..516fa79 100644 (file)
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -31,17 +31,11 @@
  * SUCH DAMAGE.
  *
  *     from: @(#)sys_process.c 7.22 (Berkeley) 5/11/91
  * SUCH DAMAGE.
  *
  *     from: @(#)sys_process.c 7.22 (Berkeley) 5/11/91

- *
- * PATCHES MAGIC                LEVEL   PATCH THAT GOT US HERE
- * --------------------         -----   ----------------------
- * CURRENT PATCH LEVEL:         1       00137
- * --------------------         -----   ----------------------
- *
- * 04 Sep 92   Paul Kranenburg         Fixed copy-on-write checking for pages
- *                                     other than anonymous (text pages, etc.)
- * 08 Apr 93   Bruce Evans             Several VM system fixes
+ *     $Id$

  */
 
  */
 

+#include <stddef.h>
+

 #define IPCREG
 #include "param.h"
 #include "proc.h"
 #define IPCREG
 #include "param.h"
 #include "proc.h"


@@ -49,6 +43,7 @@
 #include "buf.h"
 #include "ptrace.h"
 
 #include "buf.h"
 #include "ptrace.h"
 

+#include "machine/eflags.h"

 #include "machine/reg.h"
 #include "machine/psl.h"
 #include "vm/vm.h"
 #include "machine/reg.h"
 #include "machine/psl.h"
 #include "vm/vm.h"


@@ -105,14 +100,17 @@ struct {
 /*
  * Process debugging system call.
  */
 /*
  * Process debugging system call.
  */

+
+struct ptrace_args {
+       int     req;
+       int     pid;
+       int     *addr;
+       int     data;
+};
+

 ptrace(curp, uap, retval)
        struct proc *curp;
 ptrace(curp, uap, retval)
        struct proc *curp;

-       register struct args {
-               int     req;
-               int     pid;
-               int     *addr;
-               int     data;
-       } *uap;
+       register struct ptrace_args *uap;

        int *retval;
 {
        struct proc *p;
        int *retval;
 {
        struct proc *p;


@@ -264,6 +262,10 @@ procxmt(p)
        register struct proc *p;
 {
        int i, *xreg, rv = 0;
        register struct proc *p;
 {
        int i, *xreg, rv = 0;

+#ifdef i386
+       int new_eflags, old_cs, old_ds, old_es, old_ss, old_eflags;
+       int *regs;
+#endif

 
        /* Are we still being traced? */
        if ((p->p_flag & STRC) == 0)
 
        /* Are we still being traced? */
        if ((p->p_flag & STRC) == 0)


@@ -307,6 +309,8 @@ procxmt(p)
                        /*
                         * XXX - the useracc check is stronger than the vm
                         * checks because the user page tables are in the map.
                        /*
                         * XXX - the useracc check is stronger than the vm
                         * checks because the user page tables are in the map.

+                        * Anyway, most of this can be removed now that COW
+                        * works.

                         */
                        if (!useracc(ipc.addr, sizeof(ipc.data), B_READ) ||
                            vm_region(&p->p_vmspace->vm_map, &addr, &size,
                         */
                        if (!useracc(ipc.addr, sizeof(ipc.data), B_READ) ||
                            vm_region(&p->p_vmspace->vm_map, &addr, &size,


@@ -333,11 +337,92 @@ procxmt(p)
        }
 
        case PT_WRITE_U:
        }
 
        case PT_WRITE_U:

+#ifdef i386
+               regs = p->p_regs;
+               /*
+                * XXX - privileged kernel state is scattered all over the
+                * user area.  Only allow write access to areas known to
+                * be safe.
+                */
+#define        GO_IF_SAFE(min, size) \
+               if ((u_int)ipc.addr >= (min) \
+                   && (u_int)ipc.addr <= (min) + (size) - sizeof(int)) \
+                       goto pt_write_u
+               /*
+                * Allow writing entire FPU state.
+                */
+               GO_IF_SAFE(offsetof(struct user, u_pcb)
+                          + offsetof(struct pcb, pcb_savefpu),
+                          sizeof(struct save87));
+               /*
+                * Allow writing ordinary registers.  Changes to segment
+                * registers and to some bits in %eflags will be silently
+                * ignored.  Such changes ought to be an error.
+                */
+/*
+ * XXX - there is no define for the base of the user area except USRSTACK.
+ * XXX - USRSTACK is not the base of the user stack.  It is the base of the
+ * user area.
+ */
+#define        USER_OFF(va)    ((u_int)(va) - USRSTACK)
+               GO_IF_SAFE(USER_OFF(regs),
+                          (curpcb->pcb_flags & FM_TRAP ? tSS + 1 : sSS + 1)
+                          * sizeof *regs);
+               ipc.error = EFAULT;
+               break;
+#else

                if ((u_int)ipc.addr > UPAGES * NBPG - sizeof(int)) {
                        ipc.error = EFAULT;
                        break;
                }
                if ((u_int)ipc.addr > UPAGES * NBPG - sizeof(int)) {
                        ipc.error = EFAULT;
                        break;
                }

+#endif
+       pt_write_u:
+#ifdef i386
+               if (curpcb->pcb_flags & FM_TRAP) {
+                       old_cs = regs[tCS];
+                       old_ds = regs[tES];
+                       old_es = regs[tES];
+                       old_ss = regs[tSS];
+                       old_eflags = regs[tEFLAGS];
+               } else {
+                       old_cs = regs[sCS];
+                       old_ss = regs[sSS];
+                       old_eflags = regs[sEFLAGS];
+               }
+#endif

                *(int *)((u_int)p->p_addr + (u_int)ipc.addr) = ipc.data;
                *(int *)((u_int)p->p_addr + (u_int)ipc.addr) = ipc.data;

+#ifdef i386
+               /*
+                * Don't allow segment registers to change (although they can
+                * be changed directly to certain values).
+                * Don't allow privileged bits in %eflags to change.  Users
+                * have privilege to change TF and NT although although they
+                * usually shouldn't.
+                * XXX - fix PT_SETREGS.
+                * XXX - simplify.  Maybe copy through a temporary struct.
+                * Watch out for problems when ipc.addr is not a multiple
+                * of the register size.
+                */
+#define EFL_UNPRIVILEGED (EFL_CF | EFL_PF | EFL_AF | EFL_ZF | EFL_SF \
+                         | EFL_TF | EFL_DF | EFL_OF | EFL_NT)
+               if (curpcb->pcb_flags & FM_TRAP) {
+                       regs[tCS] = old_cs;
+                       regs[tDS] = old_ds;
+                       regs[tES] = old_es;
+                       regs[tSS] = old_es;
+                       new_eflags = regs[tEFLAGS];
+                       regs[tEFLAGS]
+                               = (new_eflags & EFL_UNPRIVILEGED)
+                                 | (old_eflags & ~EFL_UNPRIVILEGED);
+               } else {
+                       regs[sCS] = old_cs;
+                       regs[sSS] = old_ss;
+                       new_eflags = regs[sEFLAGS];
+                       regs[sEFLAGS]
+                               = (new_eflags & EFL_UNPRIVILEGED)
+                                 | (old_eflags & ~EFL_UNPRIVILEGED);
+               }
+#endif

                break;
 
        case PT_CONTINUE:
                break;
 
        case PT_CONTINUE:


@@ -418,7 +503,7 @@ procxmt(p)
        wakeup((caddr_t)&ipc);
 
        if (rv == 2)
        wakeup((caddr_t)&ipc);
 
        if (rv == 2)

-               exit(p, 0);     /*???*/
+               kexit(p, 0);    /*???*/

 
        return rv;
 }
 
        return rv;
 }


@@ -426,15 +511,18 @@ procxmt(p)
 /*
  * Enable process profiling system call.
  */
 /*
  * Enable process profiling system call.
  */

+
+struct profil_args {
+       short   *bufbase;       /* base of data buffer */
+       unsigned bufsize;       /* size of data buffer */
+       unsigned pcoffset;      /* pc offset (for subtraction) */
+       unsigned pcscale;       /* scaling factor for offset pc */
+};
+

 /* ARGSUSED */
 profil(p, uap, retval)
        struct proc *p;
 /* ARGSUSED */
 profil(p, uap, retval)
        struct proc *p;

-       register struct args {
-               short   *bufbase;       /* base of data buffer */
-               unsigned bufsize;       /* size of data buffer */
-               unsigned pcoffset;      /* pc offset (for subtraction) */
-               unsigned pcscale;       /* scaling factor for offset pc */
-       } *uap;
+       register struct profil_args *uap;

        int *retval;
 {
        /* from looking at man pages, and include files, looks like
        int *retval;
 {
        /* from looking at man pages, and include files, looks like