Path: csiph.com!1.us.feeder.erje.net!feeder.erje.net!1.eu.feeder.erje.net!enother.net!enother.net!news.mixmin.net!aioe.org!bofh.it!news.nic.it!robomod From: Greg Kroah-Hartman Newsgroups: linux.kernel Subject: [PATCH 4.4 118/118] ia64: copy_from_user() should zero the destination on access_ok() failure Date: Thu, 22 Sep 2016 19:40:03 +0200 Message-ID: References: X-Original-To: linux-kernel@vger.kernel.org X-Mailer: git-send-email 2.10.0 User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 44 Organization: linux.* mail to news gateway X-Original-Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro X-Original-Date: Thu, 22 Sep 2016 19:30:18 +0200 X-Original-Message-ID: <20160922172944.690522915@linuxfoundation.org> X-Original-References: <20160922172938.643879685@linuxfoundation.org> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1489147 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit a5e541f796f17228793694d64b507f5f57db4cd7 upstream. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- arch/ia64/include/asm/uaccess.h | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) --- a/arch/ia64/include/asm/uaccess.h +++ b/arch/ia64/include/asm/uaccess.h @@ -263,17 +263,15 @@ __copy_from_user (void *to, const void _ __cu_len; \ }) -#define copy_from_user(to, from, n) \ -({ \ - void *__cu_to = (to); \ - const void __user *__cu_from = (from); \ - long __cu_len = (n); \ - \ - __chk_user_ptr(__cu_from); \ - if (__access_ok(__cu_from, __cu_len, get_fs())) \ - __cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len); \ - __cu_len; \ -}) +static inline unsigned long +copy_from_user(void *to, const void __user *from, unsigned long n) +{ + if (likely(__access_ok(from, n, get_fs()))) + n = __copy_user((__force void __user *) to, from, n); + else + memset(to, 0, n); + return n; +} #define __copy_in_user(to, from, size) __copy_user((to), (from), (size))