From mboxrd@z Thu Jan 1 00:00:00 1970 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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D1842CCD192 for ; Mon, 13 Oct 2025 21:57:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0296D8E00AA; Mon, 13 Oct 2025 17:56:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EF2AC8E00A2; Mon, 13 Oct 2025 17:56:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D6E578E00AA; Mon, 13 Oct 2025 17:56:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id BE9358E00A2 for ; Mon, 13 Oct 2025 17:56:57 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 8AAA8160652 for ; Mon, 13 Oct 2025 21:56:57 +0000 (UTC) X-FDA: 83994451674.22.4603C21 Received: from mail-pj1-f46.google.com (mail-pj1-f46.google.com [209.85.216.46]) by imf30.hostedemail.com (Postfix) with ESMTP id A456C80015 for ; Mon, 13 Oct 2025 21:56:55 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=rivosinc.com header.s=google header.b=UizS6CVe; spf=pass (imf30.hostedemail.com: domain of debug@rivosinc.com designates 209.85.216.46 as permitted sender) smtp.mailfrom=debug@rivosinc.com; dmarc=pass (policy=none) header.from=rivosinc.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1760392615; a=rsa-sha256; cv=none; b=XnqKQSrzoKbNID3+rWDysx6uRsCp8WQZVSYCXTsB724wtd+3FppqAPMo4WV3aWjoTt1Jln NMGlWSNRIyX8SeU4XmLcuCvQjsCJOy36XNNmMDda8RpeyiGqm2i2Gvg3PcVeDFCrsKUWcg /OlcI2OMiTAY+3nrnc0Q9g53khWb9bo= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=rivosinc.com header.s=google header.b=UizS6CVe; spf=pass (imf30.hostedemail.com: domain of debug@rivosinc.com designates 209.85.216.46 as permitted sender) smtp.mailfrom=debug@rivosinc.com; dmarc=pass (policy=none) header.from=rivosinc.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1760392615; 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=Dbof0LYINd4D+dAMCbCh8LGflH6StFg2c2dYAuc2+YY=; b=NqeNcBvW9BNektc1YwrtDEKclSQdtvdBC9nsVYyyPyw08NKoLfyRN5jcXwIswwhmLYbi/t n+SN2fC4M6n+oR9Vzd1zLWXJCMEpzDEbUOPT39RCenUKrdNaqJDBZcxUP78yGMxQebItH+ hTcfGmGX9NAgPARsXRzNdldimRCF27g= Received: by mail-pj1-f46.google.com with SMTP id 98e67ed59e1d1-3304a57d842so3771526a91.3 for ; Mon, 13 Oct 2025 14:56:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc.com; s=google; t=1760392614; x=1760997414; darn=kvack.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=Dbof0LYINd4D+dAMCbCh8LGflH6StFg2c2dYAuc2+YY=; b=UizS6CVekP3KAm5kGzM0/kBe4VB4ttCjE/TzaO2ZwI/AtzBJvVMWUacUf1ZhN01KKt YFFJRleeMRUBnKJxv2vetWa0Nt5RHnoVNtmeeQtjhynWhMvle1AA3DyPOqj902FGs2lj cdkNSyuf/NUVqe3ZmU9lncTz15ZYCgRHfENGHFZF1MhZDaOFPgYGNaa7gj6pW5F+1MKZ gpv6KmR0DlTDZOltHm31mKd3crjhHSPPyGHKapEyS+VeQpdkulSwcIiBMe2WMzWSzxmE pITfJAFoI34JyPG5qAmVqOlAEzwlXlCmhTZmLdsd4moMgjYCmw6vAvq+2k0rT08MZSRK mbMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760392614; x=1760997414; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Dbof0LYINd4D+dAMCbCh8LGflH6StFg2c2dYAuc2+YY=; b=HXmo2y6zbTA55TMWAev4B/ff8x0EtPwSpbTYdmF9C0kN5ugem+Bwc1F/WTwwExGUCX eudNdjZtuPd6bHOb9TBwAknpCOOdzc937PGIVv4FgSgYJB/Es+ntfsqTN2SvRuuoJ1lt QfBVTMVvnAuTUz+cJSwQGeYUoxuhk0DO8GiyWPr5K/NsLLeN6UXCDz4XGDjwiEV5nbG+ Y3GzdWHjw6WftvJlhJpofhi8qnH5CU0/Vmzi2yDueOchn7g8n6o9hUyLYPYzOC9mN2lU f1QMsGNp4B2drECBtfpESqskVlryo/dL9y+uHjLQ1sFVIygII1fSU/1btYdnqRxpjKSD 02KA== X-Forwarded-Encrypted: i=1; AJvYcCWzIxTi2Kt8Nizb+RU67uoFLRC1bldILq7MpRab2cyE8Q2k7lupbYVyk4MWEo+VYFb9coGS1+Gysg==@kvack.org X-Gm-Message-State: AOJu0YyeHcQVlDWfw8qeKq/WjvVySVWYh7mA3+69sy7L89nSrRZetVGv 9cFm1Ucr8gIKRvdGeiwLEs++aTLxR+YKqfiovHqDkJ1h1BcydbG8EOqEjJgzFPxaT3o= X-Gm-Gg: ASbGncv92xbJlsaCiH8GHHMyjE9+gDn9CUfEH6f5zS6POxwlcop2s+OskOKeF1wIZbd xU5t13uK1IH/Np5nSBe6YoM83BQPmRddHmsAgetosYVeuxoLRXHf0Lng0hKipyLIR+oii9oDCzp Xn0bMxwiaKJ/ba1X3+kS7tlR3khWd8dFjPXLP3nEoewaJinkBLfxPSIifxZV9gBhn0n2RwSs4Wo +b0dg1SojUZm4rHijqUnycENzd5jFL3YXpz4IGpMjTasOTCRppdEwROVujrK5AXacdmWT0LoKz7 I/pprRgQxkWujFdBdNA85jc0dKcT7CibdivkoIHUykwJXsipfx1SREz+UWkysjhhmUEYEacp/6e Rzi95wPwQ9IpKQ+L9t9Urb8XQt4Fe1skqezARpv24HFosmZIEV2lck1KFMnmyIg== X-Google-Smtp-Source: AGHT+IFIgzSXP/F7dXAlqZ2LJnQcYWDmxG36zDHOJJWTPgNoALO0OawBjU2puecWF73352ydInfFiA== X-Received: by 2002:a17:90b:1d8b:b0:32b:355a:9de with SMTP id 98e67ed59e1d1-33b513d005amr30620659a91.32.1760392614454; Mon, 13 Oct 2025 14:56:54 -0700 (PDT) Received: from debug.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-33b626bb49esm13143212a91.12.2025.10.13.14.56.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Oct 2025 14:56:54 -0700 (PDT) From: Deepak Gupta Date: Mon, 13 Oct 2025 14:56:17 -0700 Subject: [PATCH v20 25/28] riscv: create a config for shadow stack and landing pad instr support MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251013-v5_user_cfi_series-v20-25-b9de4be9912e@rivosinc.com> References: <20251013-v5_user_cfi_series-v20-0-b9de4be9912e@rivosinc.com> In-Reply-To: <20251013-v5_user_cfi_series-v20-0-b9de4be9912e@rivosinc.com> To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes , Paul Walmsley , Palmer Dabbelt , Albert Ou , Conor Dooley , Rob Herring , Krzysztof Kozlowski , Arnd Bergmann , Christian Brauner , Peter Zijlstra , Oleg Nesterov , Eric Biederman , Kees Cook , Jonathan Corbet , Shuah Khan , Jann Horn , Conor Dooley , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Andreas Hindborg , Alice Ryhl , Trevor Gross , Benno Lossin Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, alistair.francis@wdc.com, richard.henderson@linaro.org, jim.shu@sifive.com, andybnac@gmail.com, kito.cheng@sifive.com, charlie@rivosinc.com, atishp@rivosinc.com, evan@rivosinc.com, cleger@rivosinc.com, alexghiti@rivosinc.com, samitolvanen@google.com, broonie@kernel.org, rick.p.edgecombe@intel.com, rust-for-linux@vger.kernel.org, Zong Li , Deepak Gupta X-Mailer: b4 0.13.0 X-Rspam-User: X-Stat-Signature: gzr1s73mb374af665dyeix4s6ds7ga6d X-Rspamd-Queue-Id: A456C80015 X-Rspamd-Server: rspam09 X-HE-Tag: 1760392615-529515 X-HE-Meta: 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 jK3xZS0T GT0Wl3gN/HMnH+nifZa1JhlgwHQ1CjJrQ/v3T2b9Q+M41vEtJJ0xQpL+4pMXQA1UvnQHj9y+Y9zSLNhm6czb+USXc7mzwskFDNP69aJkEC9FyOlxNpNsmkrxO/xK33rFLBQwolzmtIobe8ArJx+66n0MrPRQrybX7K+ueBPfYmxRXPP+NOPYKbie4LalPlaWP/FiL0rlaOuND5Ye3DJUoGu9oO8YrLqKJIb5EhXGM1COxtP/u13Gd1nk6iblybiNfD5i/l7i+plYPIeufVB4czNSEpajrBoMpDffL3jxBW+33ZTWP0WS0a9jQK0yjKTxbkXgxsYQKkohremVTLqLrWY00+v6vLCQMtFCpu0ksQEcc0FBl047ZZxea51jOmge6KVuBMyzhTtow7/X+W/+/DlBICazcDzZKgn8ZEXuqJ21bbktBrLU94gNvjOFyeAPEO3lxGVzhrW5RiBBnwvBtwEh+j6SDm5ClrBfn 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: This patch creates a config for shadow stack support and landing pad instr support. Shadow stack support and landing instr support can be enabled by selecting `CONFIG_RISCV_USER_CFI`. Selecting `CONFIG_RISCV_USER_CFI` wires up path to enumerate CPU support and if cpu support exists, kernel will support cpu assisted user mode cfi. If CONFIG_RISCV_USER_CFI is selected, select `ARCH_USES_HIGH_VMA_FLAGS`, `ARCH_HAS_USER_SHADOW_STACK` and DYNAMIC_SIGFRAME for riscv. Reviewed-by: Zong Li Signed-off-by: Deepak Gupta --- arch/riscv/Kconfig | 21 +++++++++++++++++++++ arch/riscv/configs/hardening.config | 4 ++++ 2 files changed, 25 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 0c6038dc5dfd..aed033e2b526 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -1146,6 +1146,27 @@ config RANDOMIZE_BASE If unsure, say N. +config RISCV_USER_CFI + def_bool y + bool "riscv userspace control flow integrity" + depends on 64BIT && $(cc-option,-mabi=lp64 -march=rv64ima_zicfiss) + depends on RISCV_ALTERNATIVE + select RISCV_SBI + select ARCH_HAS_USER_SHADOW_STACK + select ARCH_USES_HIGH_VMA_FLAGS + select DYNAMIC_SIGFRAME + help + Provides CPU assisted control flow integrity to userspace tasks. + Control flow integrity is provided by implementing shadow stack for + backward edge and indirect branch tracking for forward edge in program. + Shadow stack protection is a hardware feature that detects function + return address corruption. This helps mitigate ROP attacks. + Indirect branch tracking enforces that all indirect branches must land + on a landing pad instruction else CPU will fault. This mitigates against + JOP / COP attacks. Applications must be enabled to use it, and old user- + space does not get protection "for free". + default n. + endmenu # "Kernel features" menu "Boot options" diff --git a/arch/riscv/configs/hardening.config b/arch/riscv/configs/hardening.config new file mode 100644 index 000000000000..089f4cee82f4 --- /dev/null +++ b/arch/riscv/configs/hardening.config @@ -0,0 +1,4 @@ +# RISCV specific kernel hardening options + +# Enable control flow integrity support for usermode. +CONFIG_RISCV_USER_CFI=y -- 2.43.0