From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71C8DC7618B for ; Sun, 28 Jul 2019 13:21:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 504A3214C6 for ; Sun, 28 Jul 2019 13:21:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726390AbfG1NVI (ORCPT ); Sun, 28 Jul 2019 09:21:08 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:51641 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726027AbfG1NUr (ORCPT ); Sun, 28 Jul 2019 09:20:47 -0400 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hrj6S-0003pu-2n; Sun, 28 Jul 2019 15:20:44 +0200 Message-Id: <20190728131648.587523358@linutronix.de> User-Agent: quilt/0.65 Date: Sun, 28 Jul 2019 15:12:52 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Andy Lutomirski , Vincenzo Frascino , Sean Christopherson , Kees Cook , Paul Bolle , Will Deacon Subject: [patch 1/5] lib/vdso/32: Remove inconsistent NULL pointer checks References: <20190728131251.622415456@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The 32bit variants of vdso_clock_gettime()/getres() have a NULL pointer check for the timespec pointer. That's inconsistent vs. 64bit. But the vdso implementation will never be consistent versus the syscall because the only case which it can handle is NULL. Any other invalid pointer will cause a segfault. So special casing NULL is not really useful. Remove it along with the superflouos syscall fallback invocation as that will return -EFAULT anyway. That also gets rid of the dubious typecast which only works because the pointer is NULL. Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation") Signed-off-by: Thomas Gleixner --- lib/vdso/gettimeofday.c | 18 ++---------------- 1 file changed, 2 insertions(+), 16 deletions(-) --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -115,9 +115,6 @@ static __maybe_unused int struct __kernel_timespec ts; int ret; - if (res == NULL) - goto fallback; - ret = __cvdso_clock_gettime(clock, &ts); if (ret == 0) { @@ -126,9 +123,6 @@ static __maybe_unused int } return ret; - -fallback: - return clock_gettime_fallback(clock, (struct __kernel_timespec *)res); } static __maybe_unused int @@ -204,10 +198,8 @@ int __cvdso_clock_getres(clockid_t clock goto fallback; } - if (res) { - res->tv_sec = 0; - res->tv_nsec = ns; - } + res->tv_sec = 0; + res->tv_nsec = ns; return 0; @@ -221,9 +213,6 @@ static __maybe_unused int struct __kernel_timespec ts; int ret; - if (res == NULL) - goto fallback; - ret = __cvdso_clock_getres(clock, &ts); if (ret == 0) { @@ -232,8 +221,5 @@ static __maybe_unused int } return ret; - -fallback: - return clock_getres_fallback(clock, (struct __kernel_timespec *)res); } #endif /* VDSO_HAS_CLOCK_GETRES */