From patchwork Thu May 20 09:20:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 445436 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 588F5C433ED for ; Thu, 20 May 2021 10:49:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 362EA61001 for ; Thu, 20 May 2021 10:49:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238273AbhETKvH (ORCPT ); Thu, 20 May 2021 06:51:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:48012 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237916AbhETKsY (ORCPT ); Thu, 20 May 2021 06:48:24 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 844B761417; Thu, 20 May 2021 09:58:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621504719; bh=7LF1dtWXlW+axmwcZhX4sjdKm1fHfGH6pqioFX8qAqs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hykW0lRB2rt/DLVDcvZeubuBmWSmmJPOnok6BtrfwolqigFnGGFyS5Om6/Y0T2sZo Qmf0ZNvp9KYgmGxdKajGOg4z4ag6yAB4g5Ut8QDQSeVYGxxMyEI6xmti5dm+7PBuDC OuHB+dEDKqgIBM9RpJkT+AQpuyuxOa+MhFiYmMeA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bill Wendling , Kees Cook , Ard Biesheuvel , Catalin Marinas , Sasha Levin Subject: [PATCH 4.9 050/240] arm64/vdso: Discard .note.gnu.property sections in vDSO Date: Thu, 20 May 2021 11:20:42 +0200 Message-Id: <20210520092110.350148404@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092108.587553970@linuxfoundation.org> References: <20210520092108.587553970@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Bill Wendling [ Upstream commit 388708028e6937f3fc5fc19aeeb847f8970f489c ] The arm64 assembler in binutils 2.32 and above generates a program property note in a note section, .note.gnu.property, to encode used x86 ISAs and features. But the kernel linker script only contains a single NOTE segment: PHDRS { text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ note PT_NOTE FLAGS(4); /* PF_R */ } The NOTE segment generated by the vDSO linker script is aligned to 4 bytes. But the .note.gnu.property section must be aligned to 8 bytes on arm64. $ readelf -n vdso64.so Displaying notes found in: .note Owner Data size Description Linux 0x00000004 Unknown note type: (0x00000000) description data: 06 00 00 00 readelf: Warning: note with invalid namesz and/or descsz found at offset 0x20 readelf: Warning: type: 0x78, namesize: 0x00000100, descsize: 0x756e694c, alignment: 8 Since the note.gnu.property section in the vDSO is not checked by the dynamic linker, discard the .note.gnu.property sections in the vDSO. Similar to commit 4caffe6a28d31 ("x86/vdso: Discard .note.gnu.property sections in vDSO"), but for arm64. Signed-off-by: Bill Wendling Reviewed-by: Kees Cook Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20210423205159.830854-1-morbo@google.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin --- arch/arm64/kernel/vdso/vdso.lds.S | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/vdso/vdso.lds.S b/arch/arm64/kernel/vdso/vdso.lds.S index beca249bc2f3..b3e6c4d5b75c 100644 --- a/arch/arm64/kernel/vdso/vdso.lds.S +++ b/arch/arm64/kernel/vdso/vdso.lds.S @@ -39,6 +39,13 @@ SECTIONS .gnu.version_d : { *(.gnu.version_d) } .gnu.version_r : { *(.gnu.version_r) } + /* + * Discard .note.gnu.property sections which are unused and have + * different alignment requirement from vDSO note sections. + */ + /DISCARD/ : { + *(.note.GNU-stack .note.gnu.property) + } .note : { *(.note.*) } :text :note . = ALIGN(16); @@ -59,7 +66,6 @@ SECTIONS PROVIDE(end = .); /DISCARD/ : { - *(.note.GNU-stack) *(.data .data.* .gnu.linkonce.d.* .sdata*) *(.bss .sbss .dynbss .dynsbss) }