From patchwork Wed Aug 28 23:27:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13782176 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2356AC71150 for ; Wed, 28 Aug 2024 23:30:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A70016B00AA; Wed, 28 Aug 2024 19:30:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A1FA06B00AC; Wed, 28 Aug 2024 19:30:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C0A16B00AD; Wed, 28 Aug 2024 19:30:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 6E55B6B00AA for ; Wed, 28 Aug 2024 19:30:21 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 00581160337 for ; Wed, 28 Aug 2024 23:30:20 +0000 (UTC) X-FDA: 82503250242.05.D80D044 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf28.hostedemail.com (Postfix) with ESMTP id 81F10C0015 for ; Wed, 28 Aug 2024 23:30:18 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=csXIYlPb; spf=pass (imf28.hostedemail.com: domain of broonie@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=broonie@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1724887730; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=+UV0KNhy1yM4MCqy+6moJq4nXq6qKyYx4onoSkTfwro=; b=NntcsbX1VEkIXbSY6mZrvELHZOEdKdngfNbHhvGlS22N6slg5nRd+iACaresvh5w716WY9 Nu3fEHcOUZO+rDz/XiRyfGQLUEqlnT2UgE3KetVxKNc4Se4azcNPimhHJoOJVudhpGKBwf unxHZIfsoeQz9BuaqLwkMvG+Bo2WwFk= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1724887730; a=rsa-sha256; cv=none; b=Y5kBpuz2pXAI81W3V3XVKyVqVTH7Shnsc6qCtfG6ZhfEZ6wXIVUecJ0f6olbbyNCavtkjx TwhfW5meZttAO+09+J/3lJvh36199mEdfyIMJF37Ve5yR7i6dBKleAQJ18Hs4zZ4G1Hxxq h1uO6uuiodNJMzN+X+63e6+unZD3Ts0= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=csXIYlPb; spf=pass (imf28.hostedemail.com: domain of broonie@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=broonie@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id C1D53CE19BB; Wed, 28 Aug 2024 23:30:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E576DC4CEC5; Wed, 28 Aug 2024 23:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724887815; bh=q8jtVg186GFJVIbjl1JCrkiZnz/oBLnR/HtHUgXvMfA=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=csXIYlPbjsq0/jESzviJXGLS5PVUMwFyPcl9Xf8tCAU3CGgzUzcSXEOOGrzJGOi4n +LVpTfKWkimkyH2gkwgyYFLAqrNxMfByqvcuy0VRXO4vSBMDQDGRLkHTzLYPfpeOy2 AyEWc7lOsYqAfbBDM8Bc6mJym3P1TCGwFH6JYwLsXtYbilIWgJGJBuUIWwEF4ruBzk Irzl16KGJZap13BwqZWYzbzXWP+4eyR9laKqpNp69phFVR0DOgEfIDlzw09zIlvjZg aqd4HA+U9jzpvZJm3UVCJjQd5uoKjF5Q0gQa5Ttxa0UAOtqwlc/QdBtfEypp/Uxek/ Eb/XXqGaqeeCg== From: Mark Brown Date: Thu, 29 Aug 2024 00:27:30 +0100 Subject: [PATCH v12 14/39] arm64/mm: Map pages for guarded control stack MIME-Version: 1.0 Message-Id: <20240829-arm64-gcs-v12-14-42fec947436a@kernel.org> References: <20240829-arm64-gcs-v12-0-42fec947436a@kernel.org> In-Reply-To: <20240829-arm64-gcs-v12-0-42fec947436a@kernel.org> To: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , Kees Cook Cc: "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , Ross Burton , Yury Khrustalev , Wilco Dijkstra , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Brown X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=1824; i=broonie@kernel.org; h=from:subject:message-id; bh=q8jtVg186GFJVIbjl1JCrkiZnz/oBLnR/HtHUgXvMfA=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBmz7KDz+A8JTqcELz4cAJ592v00no+g1aVltB8BmzS YLVlld6JATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZs+ygwAKCRAk1otyXVSH0GfJB/ 49HQhF+L8EiPWM7v3hZ36OyfEAtuZYOAa7yxbdtNlpOsOKuJCieWaGUjCl4V7oMxDUXRoMqIYkJ2Y7 0UjpPJ2A/OzEmFWXJzvSlVo9eCTfasoJ4KB8k9tuDNt/wmQ2GuY7C+9u0ds83AmngnuKcfDeqVE0VW 8xDc5pxqMmvZE+kh51h7AXaa+kMQTlm7Dnb4gtNI554joq08SMIgk7fZKptpoJne0VPkT1C7gUBfTG r3ZYOx8kpQ6ZA2hstniXP3cfObhdDaqIBtvnccak5YaFOo4qP9sUvzJOoHVrguVBLRswG/5kNuET2U 0gXB7BzsUfSt94B6y9IbRGc5knJOAA X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-Stat-Signature: 6999pck77kzzg3bqd586bhexyfonmnhs X-Rspamd-Queue-Id: 81F10C0015 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1724887818-879814 X-HE-Meta: U2FsdGVkX19fgf12AS9SnL6w/36qkIHURkq1U/fqufCr5+QF3/LF9dGptTu13KASNMIF6gqSh/rUKrnxvOAXGoy9CYxL7qfosLgSUb6WBaVfG/5lJp0Dv3q957tKOR/vWnkvvd22JTHtVLN0blRievl6DMxpLkoBjJHhwGbLuLhYDt/Gw76ykvVD1Tcb0TznD8gryMGs4WIQQ0mrWTi4GG6is4LpyqSVKhl1fom6+jMvd6fjrWQ61jGTWgJd+0NNAtg/27Wn/G5EAYZC5jqH6K+ZdUm1Qkjh0LDArYSgQk0JUKFqiAJLhaozZG2GkVNi1uxJiow+h47ncWwCc6UEXVH047mA3yYbQVXEMUEydXIexaQI9LALGSVrWEp7tF9B9PSDQxJj87z5Ki8ZtVb2e9e0f3UgYU2VhsI17zxT7o+uiCFYSUmAEpkWDU8PBuYfYFKgbVMdP2vQkjy3GnCQNViBS0OrJygkBxsehal32mhgeoKW4Zzqiv0CF7+obqepHgZh+Mo4vrEAMy2PrVw6VPQW3rn6teIS80avuRN0te9TIRPUPdkyB1NewoHTysHn/9E1UbcxrivVqIhSdnADpKqRdEfQw4iyg3sMVSqyESRCrGXCFlo+TmeDmSPG8LVjq+MW7cxhGntRIFVrt52+wH0Gfxtg3ibPpA829UL7T25HckiuZ2khiJI/rJH1wkPgnDPP7c0AGPdAdlMYyhdGXooesgT1CYQd30VFksd87Z0azM7YVBlBJL6lr8YJyX9zMFGnSrZsdu+YUuDCLVdA4DDqIWWH6h/uoWDHKwOHmPpS/819oXX7sxEOCV9Z+dqb4SAkG4F862Y0zpZRx1UYvA2MZffKdnmOwsD9pXidZKVzjFINsbJ+HnQkYgkVSLlngirefmhiWw//QlYpWVRK/Ki0AKBCy39Y8oAA22Idc+5GOoWOPP5LFxmVWbvNOGD3ygCWoXM0rM+eDDdv2KX BthCLAaJ gBzbmy1lg9835BYIKU8tqSbeoafSONse2Ft+NYho24Ghzq7iE+aQ0808W2Rvld29BrYcZqReuzO0XkqycRrvIqbJS1gQRP0XIysglx9sOtOJ6+bCvYEKmHyfZjEsddQqcn7i8igXRtwFm8yHnN4Nfj/63deBn8k6kGG+JhdN2A3VycGldCjzhJ1wKy4+uLifQqEWTDVIFYlqVhzm1n7ZMkjhbFFLKiTbzjuZIytuknoEsOlobg5Ar3NcEEW8qpIfV9D7qHnQcu+ELHYBd//GnXMfTJbLEHYZ0upG+cewTIvTL35ImP73giYlkIW/qvZG0bZDFK/m+Wk356wcbbx73rPh/QLoL1OkYYFsTEUa4VU7lHBt08piXj1s6znqdFU3Rl0QwjibgjBQxcIZIuQ1ubXXC366ZAwlzltUErWa2Tj8U7kIQvCJ4TxN8LVsM5Vz8PeKlbly6juZqbFmyyJlmYhsL5A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Map pages flagged as being part of a GCS as such rather than using the full set of generic VM flags. This is done using a conditional rather than extending the size of protection_map since that would make for a very sparse array. Reviewed-by: Thiago Jung Bauermann Reviewed-by: Catalin Marinas Signed-off-by: Mark Brown --- arch/arm64/include/asm/mman.h | 9 +++++++++ arch/arm64/mm/mmap.c | 9 ++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h index c21849ffdd88..37dfd2882f04 100644 --- a/arch/arm64/include/asm/mman.h +++ b/arch/arm64/include/asm/mman.h @@ -61,6 +61,15 @@ static inline bool arch_validate_flags(unsigned long vm_flags) return false; } + if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) { + /* An executable GCS isn't a good idea. */ + if (vm_flags & VM_EXEC) + return false; + + /* The memory management core should prevent this */ + VM_WARN_ON(vm_flags & VM_SHARED); + } + return true; } diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index 642bdf908b22..5943898f366b 100644 --- a/arch/arm64/mm/mmap.c +++ b/arch/arm64/mm/mmap.c @@ -83,8 +83,15 @@ arch_initcall(adjust_protection_map); pgprot_t vm_get_page_prot(unsigned long vm_flags) { - pteval_t prot = pgprot_val(protection_map[vm_flags & + pteval_t prot; + + /* Short circuit GCS to avoid bloating the table. */ + if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) { + prot = _PAGE_GCS_RO; + } else { + prot = pgprot_val(protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]); + } if (vm_flags & VM_ARM64_BTI) prot |= PTE_GP;