From patchwork Mon Feb 28 13:06:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 51443 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 8C06C385842C for ; Mon, 28 Feb 2022 13:07:46 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8C06C385842C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1646053666; bh=aVPnnGG4dBHnCUy/WAwu4DBwEsaF0PXrGXGfE7zVW88=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=WQ7f0e7237HTfwRmiLVhAH9kBKyV57KyiiTmnenffEx1e8q/kmvr4ZKevB+dk77sy 2Nlwdtm6/q+fZsJHfqrv7VLJHwsEO3GXwdFxQu9BmAb8wvBO/VBnEUHDmDp6a5xtug o3bHbq7TmleEmGq2eSKtA2ogBJ80o+hpiUbElUG4= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by sourceware.org (Postfix) with ESMTPS id 586053858C83 for ; Mon, 28 Feb 2022 13:07:26 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 586053858C83 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6359E612CA; Mon, 28 Feb 2022 13:07:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 434FEC340E7; Mon, 28 Feb 2022 13:07:22 +0000 (UTC) To: Catalin Marinas , Will Deacon Subject: [PATCH v10 0/2] arm64: Enable BTI for the executable as well as the interpreter Date: Mon, 28 Feb 2022 13:06:04 +0000 Message-Id: <20220228130606.1070960-1-broonie@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2008; h=from:subject; bh=3D39ey04d2tSNbYQJqs5wQw0sel+gm4JWNwn6CjOQDE=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBiHMi78Ns5UeAT/TGmHQuigmHVKkTD9PzzsXgY1IG5 ZD50ZaGJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYhzIuwAKCRAk1otyXVSH0IewB/ 0Q7xcFWIflR0OS+UJ9X62BLVivIDZjb9fXEwAcXQ9yjpJjvK0kO/C5eUxUAjrbmWCIf3vYcfqzViBe cjiDZ4ZZ6sRBTT7fdqIthTIm1/FI1vJl/skbbtPgx1gSoWZ1Z3JxRUVxXspBKP8iV0eSa8jzmSEeB3 EdkOm5zAkbl9baqLWPEtz7VtMUGC42/ZaVGhBOVFaq4pX2MuV5pvLH38TKS5n6TDwfDrBXeDO6JtxN df5S+oM9zUStWZcyNW+tmrWm7ytNIaa8jua3lgjlNbNm9+TebxmavpUhSuUN/GdS8cSi2MR3WVIisa R8jp02hcLXFpCsxnidTaAQnwA74Zo/ X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mark Brown via Libc-alpha From: Mark Brown Reply-To: Mark Brown Cc: linux-arch@vger.kernel.org, Yu-cheng Yu , libc-alpha@sourceware.org, Kees Cook , Szabolcs Nagy , Jeremy Linton , Mark Brown , linux-arm-kernel@lists.infradead.org Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Deployments of BTI on arm64 have run into issues interacting with systemd's MemoryDenyWriteExecute feature. Currently for dynamically linked executables the kernel will only handle architecture specific properties like BTI for the interpreter, the expectation is that the interpreter will then handle any properties on the main executable. For BTI this means remapping the executable segments PROT_EXEC | PROT_BTI. This interacts poorly with MemoryDenyWriteExecute since that is implemented using a seccomp filter which prevents setting PROT_EXEC on already mapped memory and lacks the context to be able to detect that memory is already mapped with PROT_EXEC. This series resolves this by providing a sysctl which when enabled will cause the kernel to handle the BTI property for both the interpreter and the main executable. v10: - Add a sysctl abi.bti_main controlling the new behaviour. v9: - Rebase onto v5.17-rc3. v8: - Rebase onto v5.17-rc1. v7: - Rebase onto v5.16-rc1. v6: - Rebase onto v5.15-rc1. v5: - Rebase onto v5.14-rc2. - Tweak changelog on patch 1. - Use the helper for interpreter/executable flag in elf.h as well. v4: - Rebase onto v5.14-rc1. v3: - Fix passing of properties for parsing by the main executable. - Drop has_interp from arch_parse_elf_property(). - Coding style tweaks. v2: - Add a patch dropping has_interp from arch_adjust_elf_prot() - Fix bisection issue with static executables on arm64 in the first patch. Mark Brown (2): elf: Allow architectures to parse properties on the main executable arm64: Enable BTI for main executable as well as the interpreter arch/arm64/include/asm/elf.h | 14 ++++++++-- arch/arm64/kernel/process.c | 52 +++++++++++++++++++++++++++--------- fs/binfmt_elf.c | 32 +++++++++++++++------- include/linux/elf.h | 4 ++- 4 files changed, 77 insertions(+), 25 deletions(-) base-commit: dfd42facf1e4ada021b939b4e19c935dcdd55566