In process_write_regs() and sigreturn(), be more strict about the bits

userland is allowed to change in psr.

diff --git a/sys/arch/m88k/include/psl.h b/sys/arch/m88k/include/psl.h
index a1f7438..a03dfa2 100644 (file)
--- a/sys/arch/m88k/include/psl.h
+++ b/sys/arch/m88k/include/psl.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: psl.h,v 1.5 2007/12/20 21:17:51 miod Exp $ */
+/*     $OpenBSD: psl.h,v 1.6 2008/07/28 17:50:09 miod Exp $ */
 /*
  * Copyright (c) 1996 Nivas Madhur
  * All rights reserved.
@@ -79,6 +79,10 @@
 #define PSR_IND                0x00000002      /* interrupt disable */
 #define PSR_SFRZ       0x00000001      /* shadow freeze */
 
+/* bits userland is not allowed to change */
+#define        PSR_USERSTATIC  (PSR_MODE | PSR_BO | PSR_SGN | PSR_SRM | PSR_SFD | \
+                        PSR_MXM | PSR_IND | PSR_SFRZ)
+
 #define FIP_V          0x00000002      /* valid */
 #define FIP_E          0x00000001      /* exception */
 #define FIP_ADDR       0xfffffffc      /* address mask */

diff --git a/sys/arch/m88k/m88k/process_machdep.c b/sys/arch/m88k/m88k/process_machdep.c
index 13a6acb..825c7a2 100644 (file)
--- a/sys/arch/m88k/m88k/process_machdep.c
+++ b/sys/arch/m88k/m88k/process_machdep.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: process_machdep.c,v 1.3 2005/05/18 16:44:41 miod Exp $ */
+/*     $OpenBSD: process_machdep.c,v 1.4 2008/07/28 17:50:11 miod Exp $ */
 
 /*
  * Copyright (c) 1993 The Regents of the University of California.
@@ -85,7 +85,13 @@ process_write_regs(p, regs)
        struct proc *p;
        struct reg *regs;
 {
-       bcopy((caddr_t)regs, (caddr_t)USER_REGS(p), sizeof(struct reg));
+       struct reg *procregs = (struct reg *)USER_REGS(p);
+       unsigned int psr = procregs->epsr;
+
+       bcopy(regs, procregs, sizeof(struct reg));
+       procregs->epsr =
+           (psr & PSR_USERSTATIC) | (regs->epsr & ~PSR_USERSTATIC);
+       
        return (0);
 }
 

diff --git a/sys/arch/m88k/m88k/sig_machdep.c b/sys/arch/m88k/m88k/sig_machdep.c
index 703c0e6..299bc75 100644 (file)
--- a/sys/arch/m88k/m88k/sig_machdep.c
+++ b/sys/arch/m88k/m88k/sig_machdep.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: sig_machdep.c,v 1.8 2007/12/31 09:23:53 martin Exp $  */
+/*     $OpenBSD: sig_machdep.c,v 1.9 2008/07/28 17:50:11 miod Exp $    */
 /*
  * Copyright (c) 1998, 1999, 2000, 2001 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -213,6 +213,9 @@ sys_sigreturn(struct proc *p, void *v, register_t *retval)
        tf = p->p_md.md_tf;
        scp = &ksc;
 
+       if ((scp->sc_regs.epsr ^ tf->tf_regs.epsr) & PSR_USERSTATIC)
+               return (EINVAL);
+
        bcopy((const void *)&scp->sc_regs, (caddr_t)&tf->tf_regs,
            sizeof(scp->sc_regs));