From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932109Ab1GLWZN (ORCPT ); Tue, 12 Jul 2011 18:25:13 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:36020 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756027Ab1GLWZM (ORCPT ); Tue, 12 Jul 2011 18:25:12 -0400 Date: Tue, 12 Jul 2011 15:24:49 -0700 From: Andrew Morton To: Akinobu Mita Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman Subject: Re: [PATCH] libfs: fix simple_attr_write on 32bit machine Message-Id: <20110712152449.08db152d.akpm@linux-foundation.org> In-Reply-To: <1310187626-2371-1-git-send-email-akinobu.mita@gmail.com> References: <1310187626-2371-1-git-send-email-akinobu.mita@gmail.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 9 Jul 2011 14:00:26 +0900 Akinobu Mita wrote: > Assume that /sys/kernel/debug/dummy64 is debugfs file created by > debugfs_create_x64(). > > # cd /sys/kernel/debug > # echo 0x1234567812345678 > dummy64 > # cat dummy64 > 0x0000000012345678 > > # echo 0x80000000 > dummy64 > # cat dummy64 > 0xffffffff80000000 > > The value more than INT_MAX cannot be written to the debugfs file > created by debugfs_create_u64 or debugfs_create_x64 on 32bit machine. > Because simple_attr_write() uses simple_strtol() for the conversion. > > To fix this, use simple_strtoll() instead. > > Signed-off-by: Akinobu Mita > Cc: Greg Kroah-Hartman > --- > fs/libfs.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/fs/libfs.c b/fs/libfs.c > index c88eab5..275ca474 100644 > --- a/fs/libfs.c > +++ b/fs/libfs.c > @@ -822,7 +822,7 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf, > goto out; > > attr->set_buf[size] = '\0'; > - val = simple_strtol(attr->set_buf, NULL, 0); > + val = simple_strtoll(attr->set_buf, NULL, 0); > ret = attr->set(attr->data, val); > if (ret == 0) > ret = len; /* on success, claim we got the whole input */ It should strictly be simple_strtoull(), but I guess that doesn't change anything. And it should always have been strict_*(), now known as kstrto*(). But that interface fix is non-back-compatible so it's too late to fix it.