[PATCH] Solaris: delete undocumented, unuseful -protect0 flag

[Alan Coopersmith]

Solaris already makes the page at address 0 inaccessible by default to
catch NULL pointer bugs, we don't need a double secret undocumented flag
to try to make our own hacky attempt at it.

As a bonus, deleting this code removes gcc warning of:

sun_init.c: In function 'xf86OpenConsole':
sun_init.c:103:17: warning: declaration of 'fd' shadows a previous local [-Wshadow]
             int fd = -1;
                 ^
sun_init.c:89:9: warning: shadowed declaration is here [-Wshadow]
     int fd;
         ^

Signed-off-by: Alan Coopersmith <alan.coopersmith at oracle.com>
---
 hw/xfree86/os-support/solaris/sun_init.c |   31 ------------------------------
 1 file changed, 31 deletions(-)

diff --git a/hw/xfree86/os-support/solaris/sun_init.c b/hw/xfree86/os-support/solaris/sun_init.c
index 16fc1b7..2e0af22 100644
--- a/hw/xfree86/os-support/solaris/sun_init.c
+++ b/hw/xfree86/os-support/solaris/sun_init.c
@@ -46,7 +46,6 @@
 #define	SOL_CONSOLE_DEV	"/dev/console"
 
 static Bool KeepTty = FALSE;
-static Bool Protect0 = FALSE;
 static Bool UseConsole = FALSE;
 
 #ifdef HAS_USL_VTS
@@ -97,27 +96,6 @@ xf86OpenConsole(void)
         if (geteuid() != 0)
             FatalError("xf86OpenConsole: Server must be suid root\n");
 
-        /* Protect page 0 to help find NULL dereferencing */
-        /* mprotect() doesn't seem to work */
-        if (Protect0) {
-            int fd = -1;
-
-            if ((fd = open("/dev/zero", O_RDONLY, 0)) < 0) {
-                xf86Msg(X_WARNING,
-                        "xf86OpenConsole: cannot open /dev/zero (%s)\n",
-                        strerror(errno));
-            }
-            else {
-                if (mmap(0, 0x1000, PROT_NONE,
-                         MAP_FIXED | MAP_SHARED, fd, 0) == MAP_FAILED)
-                    xf86Msg(X_WARNING,
-                            "xf86OpenConsole: failed to protect page 0 (%s)\n",
-                            strerror(errno));
-
-                close(fd);
-            }
-        }
-
 #ifdef HAS_USL_VTS
 
         /*
@@ -371,15 +349,6 @@ xf86ProcessArgument(int argc, char **argv, int i)
     }
 
     /*
-     * Undocumented flag to protect page 0 from read/write to help catch NULL
-     * pointer dereferences.  This is purely a debugging flag.
-     */
-    if (!strcmp(argv[i], "-protect0")) {
-        Protect0 = TRUE;
-        return 1;
-    }
-
-    /*
      * Use /dev/console as the console device.
      */
     if (!strcmp(argv[i], "-C")) {
-- 
1.7.9.2