put_compat_rusage(): switch to copy_to_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

kernel/compat.c

@@ -406,25 +406,27 @@ COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
 
 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 {
-	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
-	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
-	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
-	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
-	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
-	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
-	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
-	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
-	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
-	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
-	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
-	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
-	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
-	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
-	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
-	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
-	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
-	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
-	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
+	struct compat_rusage r32;
+	memset(&r32, 0, sizeof(r32));
+	r32.ru_utime.tv_sec = r->ru_utime.tv_sec;
+	r32.ru_utime.tv_usec = r->ru_utime.tv_usec;
+	r32.ru_stime.tv_sec = r->ru_stime.tv_sec;
+	r32.ru_stime.tv_usec = r->ru_stime.tv_usec;
+	r32.ru_maxrss = r->ru_maxrss;
+	r32.ru_ixrss = r->ru_ixrss;
+	r32.ru_idrss = r->ru_idrss;
+	r32.ru_isrss = r->ru_isrss;
+	r32.ru_minflt = r->ru_minflt;
+	r32.ru_majflt = r->ru_majflt;
+	r32.ru_nswap = r->ru_nswap;
+	r32.ru_inblock = r->ru_inblock;
+	r32.ru_oublock = r->ru_oublock;
+	r32.ru_msgsnd = r->ru_msgsnd;
+	r32.ru_msgrcv = r->ru_msgrcv;
+	r32.ru_nsignals = r->ru_nsignals;
+	r32.ru_nvcsw = r->ru_nvcsw;
+	r32.ru_nivcsw = r->ru_nivcsw;
+	if (copy_to_user(ru, &r32, sizeof(r32)))
 		return -EFAULT;
 	return 0;
 }