sys32_execve fix

[Carsten Langgaard <carstenl@mips.com>]

The following test fails on the 64-bit kernel:

#include <unistd.h>
#include <errno.h>

main(void)
{
        int ret;

        ret = execve("/bin/ls", NULL, NULL);
        printf("ret = %d, errno = %d\n", ret, errno);
}


The problem is that "nargs" in arch/mips64/kernel/linux32.c fails when
argv is NULL, the patch below should fix the problem:

/Carsten



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Index: arch/mips64/kernel/linux32.c
===================================================================
RCS file: /cvs/linux/arch/mips64/kernel/linux32.c,v
retrieving revision 1.42.2.6
diff -u -r1.42.2.6 linux32.c
--- arch/mips64/kernel/linux32.c        2002/07/01 00:17:14     1.42.2.6
+++ arch/mips64/kernel/linux32.c        2002/07/22 13:49:33
@@ -411,12 +411,14 @@
        int n, ret;
 
        n = 0;
+       ptr = NULL;
        do {
                /* egcs is stupid */
                if (!access_ok(VERIFY_READ, arg, sizeof (unsigned int)))
                        return -EFAULT;
-               if (IS_ERR(ret = __get_user((long)ptr,(int *)A(arg))))
-                       return ret;
+               if (arg)
+                       if (IS_ERR(ret = __get_user((long)ptr,(int *)A(arg))))
+                               return ret;
                if (ap)         /* no access_ok needed, we allocated */
                        if (IS_ERR(ret = __put_user(ptr, ap++)))
                                return ret;