parisc: sync compat getdents

Add VERIFY_WRITE check in the beginning like compat_sys_getdents() EFAULT on
parisc if put_user() fails.
Signed-off-by: NAlexandr Andreev <aandreev@openvz.org>
Signed-off-by: NAlexey Dobriyan <adobriyan@openvz.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Grant Grundler <grundler@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>

arch/parisc/kernel/sys_parisc32.c

@@ -350,6 +350,10 @@ sys32_getdents (unsigned int fd, void __user * dirent, unsigned int count)
 	struct getdents32_callback buf;
 	int error;
 
+	error = -EFAULT;
+	if (!access_ok(VERIFY_WRITE, dirent, count))
+		goto out;
+
 	error = -EBADF;
 	file = fget(fd);
 	if (!file)
@@ -366,8 +370,10 @@ sys32_getdents (unsigned int fd, void __user * dirent, unsigned int count)
 	error = buf.error;
 	lastdirent = buf.previous;
 	if (lastdirent) {
-		put_user(file->f_pos, &lastdirent->d_off);
-		error = count - buf.count;
+		if (put_user(file->f_pos, &lastdirent->d_off))
+			error = -EFAULT;
+		else
+			error = count - buf.count;
 	}
 
 out_putf: