From mboxrd@z Thu Jan 1 00:00:00 1970 From: riel@redhat.com Date: Fri, 19 May 2017 21:26:36 +0000 Subject: [PATCH 5/5] sh64: ascii armor the sh64 boot init stack canary Message-Id: <20170519212636.30440-6-riel@redhat.com> List-Id: References: <20170519212636.30440-1-riel@redhat.com> In-Reply-To: <20170519212636.30440-1-riel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org From: Rik van Riel Use the ascii-armor canary to prevent unterminated C string overflows from being able to successfully overwrite the canary, even if they somehow obtain the canary value. Inspired by execshield ascii-armor and PaX/grsecurity. Signed-off-by: Rik van Riel --- arch/sh/include/asm/stackprotector.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/sh/include/asm/stackprotector.h b/arch/sh/include/asm/stackprotector.h index d9df3a76847c..141515a43b78 100644 --- a/arch/sh/include/asm/stackprotector.h +++ b/arch/sh/include/asm/stackprotector.h @@ -19,6 +19,7 @@ static __always_inline void boot_init_stack_canary(void) /* Try to get a semi random initial value. */ get_random_bytes(&canary, sizeof(canary)); canary ^= LINUX_VERSION_CODE; + canary &= CANARY_MASK; current->stack_canary = canary; __stack_chk_guard = current->stack_canary; -- 2.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 From: riel@redhat.com (riel at redhat.com) Date: Fri, 19 May 2017 17:26:36 -0400 Subject: [PATCH 5/5] sh64: ascii armor the sh64 boot init stack canary In-Reply-To: <20170519212636.30440-1-riel@redhat.com> References: <20170519212636.30440-1-riel@redhat.com> Message-ID: <20170519212636.30440-6-riel@redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Rik van Riel Use the ascii-armor canary to prevent unterminated C string overflows from being able to successfully overwrite the canary, even if they somehow obtain the canary value. Inspired by execshield ascii-armor and PaX/grsecurity. Signed-off-by: Rik van Riel --- arch/sh/include/asm/stackprotector.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/sh/include/asm/stackprotector.h b/arch/sh/include/asm/stackprotector.h index d9df3a76847c..141515a43b78 100644 --- a/arch/sh/include/asm/stackprotector.h +++ b/arch/sh/include/asm/stackprotector.h @@ -19,6 +19,7 @@ static __always_inline void boot_init_stack_canary(void) /* Try to get a semi random initial value. */ get_random_bytes(&canary, sizeof(canary)); canary ^= LINUX_VERSION_CODE; + canary &= CANARY_MASK; current->stack_canary = canary; __stack_chk_guard = current->stack_canary; -- 2.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757260AbdESVgx (ORCPT ); Fri, 19 May 2017 17:36:53 -0400 Received: from shelob.surriel.com ([96.67.55.147]:35590 "EHLO shelob.surriel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753208AbdESVgu (ORCPT ); Fri, 19 May 2017 17:36:50 -0400 From: riel@redhat.com To: linux-kernel@vger.kernel.org Cc: danielmicay@gmail.com, tytso@mit.edu, keescook@chromium.org, hpa@zytor.com, luto@amacapital.net, mingo@kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux-sh@vger.kernel.org, ysato@users.sourceforge.jp Subject: [PATCH 5/5] sh64: ascii armor the sh64 boot init stack canary Date: Fri, 19 May 2017 17:26:36 -0400 Message-Id: <20170519212636.30440-6-riel@redhat.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170519212636.30440-1-riel@redhat.com> References: <20170519212636.30440-1-riel@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rik van Riel Use the ascii-armor canary to prevent unterminated C string overflows from being able to successfully overwrite the canary, even if they somehow obtain the canary value. Inspired by execshield ascii-armor and PaX/grsecurity. Signed-off-by: Rik van Riel --- arch/sh/include/asm/stackprotector.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/sh/include/asm/stackprotector.h b/arch/sh/include/asm/stackprotector.h index d9df3a76847c..141515a43b78 100644 --- a/arch/sh/include/asm/stackprotector.h +++ b/arch/sh/include/asm/stackprotector.h @@ -19,6 +19,7 @@ static __always_inline void boot_init_stack_canary(void) /* Try to get a semi random initial value. */ get_random_bytes(&canary, sizeof(canary)); canary ^= LINUX_VERSION_CODE; + canary &= CANARY_MASK; current->stack_canary = canary; __stack_chk_guard = current->stack_canary; -- 2.9.3