From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: [PATCH 14/29] vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA Date: Thu, 26 Sep 2019 10:55:47 -0700 Message-ID: <20190926175602.33098-15-keescook@chromium.org> References: <20190926175602.33098-1-keescook@chromium.org> Return-path: In-Reply-To: <20190926175602.33098-1-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org To: Thomas Gleixner Cc: Kees Cook , Rick Edgecombe , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Arnd Bergmann , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-c6x-dev@linux-c6x.org, Yoshinori Sato , Michal Simek , linux-parisc@vger.kernel.org, linux-xtensa@linux-xtensa.org, x86@kernel.org, linux-kernel@vger.kernel.org List-Id: linux-arch.vger.kernel.org Many architectures have an EXCEPTION_TABLE that needs only to be read-only. As such, it should live in RO_DATA. This creates a macro to identify this case for the architectures that can move EXCEPTION_TABLE into RO_DATA. Signed-off-by: Kees Cook --- include/asm-generic/vmlinux.lds.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index d57a28786bb8..35a6cba39d9f 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -69,6 +69,17 @@ #define NOTES_HEADERS_RESTORE #endif +/* + * Some architectures have non-executable read-only exception tables. + * They can be added to the RO_DATA segment by specifying their desired + * alignment. + */ +#ifdef RO_DATA_EXCEPTION_TABLE_ALIGN +#define RO_DATA_EXCEPTION_TABLE EXCEPTION_TABLE(RO_DATA_EXCEPTION_TABLE_ALIGN) +#else +#define RO_DATA_EXCEPTION_TABLE +#endif + /* Align . to a 8 byte boundary equals to maximum function alignment. */ #define ALIGN_FUNCTION() . = ALIGN(8) @@ -508,6 +519,7 @@ __stop___modver = .; \ } \ \ + RO_DATA_EXCEPTION_TABLE \ NOTES \ \ . = ALIGN((align)); \ -- 2.17.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f195.google.com ([209.85.210.195]:39539 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728079AbfIZR41 (ORCPT ); Thu, 26 Sep 2019 13:56:27 -0400 Received: by mail-pf1-f195.google.com with SMTP id v4so2257565pff.6 for ; Thu, 26 Sep 2019 10:56:27 -0700 (PDT) From: Kees Cook Subject: [PATCH 14/29] vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA Date: Thu, 26 Sep 2019 10:55:47 -0700 Message-ID: <20190926175602.33098-15-keescook@chromium.org> In-Reply-To: <20190926175602.33098-1-keescook@chromium.org> References: <20190926175602.33098-1-keescook@chromium.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Thomas Gleixner Cc: Kees Cook , Rick Edgecombe , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Arnd Bergmann , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-c6x-dev@linux-c6x.org, Yoshinori Sato , Michal Simek , linux-parisc@vger.kernel.org, linux-xtensa@linux-xtensa.org, x86@kernel.org, linux-kernel@vger.kernel.org Message-ID: <20190926175547.WPdSTiDj9WOljCLAuU7xgj3tGO_0U5fZsCcHeNgi1d8@z> Many architectures have an EXCEPTION_TABLE that needs only to be read-only. As such, it should live in RO_DATA. This creates a macro to identify this case for the architectures that can move EXCEPTION_TABLE into RO_DATA. Signed-off-by: Kees Cook --- include/asm-generic/vmlinux.lds.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index d57a28786bb8..35a6cba39d9f 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -69,6 +69,17 @@ #define NOTES_HEADERS_RESTORE #endif +/* + * Some architectures have non-executable read-only exception tables. + * They can be added to the RO_DATA segment by specifying their desired + * alignment. + */ +#ifdef RO_DATA_EXCEPTION_TABLE_ALIGN +#define RO_DATA_EXCEPTION_TABLE EXCEPTION_TABLE(RO_DATA_EXCEPTION_TABLE_ALIGN) +#else +#define RO_DATA_EXCEPTION_TABLE +#endif + /* Align . to a 8 byte boundary equals to maximum function alignment. */ #define ALIGN_FUNCTION() . = ALIGN(8) @@ -508,6 +519,7 @@ __stop___modver = .; \ } \ \ + RO_DATA_EXCEPTION_TABLE \ NOTES \ \ . = ALIGN((align)); \ -- 2.17.1