From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id C5F676B026A for ; Fri, 25 May 2018 13:21:28 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id y82-v6so3957692wmb.5 for ; Fri, 25 May 2018 10:21:28 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id 16-v6sor12889893wrt.73.2018.05.25.10.21.27 for (Google Transport Security); Fri, 25 May 2018 10:21:27 -0700 (PDT) From: Andrey Konovalov Subject: [PATCH v3 5/6] lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user Date: Fri, 25 May 2018 19:21:15 +0200 Message-Id: <011bbed9ae9404e2f8939e2bcda459387038089f.1527268727.git.andreyknvl@google.com> In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Al Viro , Andrey Konovalov , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya strncpy_from_user and strnlen_user accept user addresses as arguments, and do not go through the same path as copy_from_user and others, so here we need to handle the case of tagged user addresses separately. Untag user pointers passed to these functions. Signed-off-by: Andrey Konovalov --- lib/strncpy_from_user.c | 2 ++ lib/strnlen_user.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index b53e1b5d80f4..97467cd2bc59 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -106,6 +106,8 @@ long strncpy_from_user(char *dst, const char __user *src, long count) if (unlikely(count <= 0)) return 0; + src = untagged_addr(src); + max_addr = user_addr_max(); src_addr = (unsigned long)src; if (likely(src_addr < max_addr)) { diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index 60d0bbda8f5e..8b5f56466e00 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -108,6 +108,8 @@ long strnlen_user(const char __user *str, long count) if (unlikely(count <= 0)) return 0; + str = untagged_addr(str); + max_addr = user_addr_max(); src_addr = (unsigned long)str; if (likely(src_addr < max_addr)) { -- 2.17.0.921.gf22659ad46-goog