From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f47.google.com (mail-ot1-f47.google.com [209.85.210.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D5C3C525E for ; Mon, 24 Jun 2024 03:23:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719199434; cv=none; b=q1iw96wl7NAZOi2YQjzslv0wW/sA5BTmU+H16a2tm6+qyEpdNx2wqDQUCQh2BXTQkLyGs/j8Of4vSNwVsLC9uGAKPjG6FrD5G2b+AMZzYMkHonh3dRVnBb4VAFK05Aw5aRxENjONOkDJozRtz6y3Ak+iTKObtEk4xkweA+ooJDc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719199434; c=relaxed/simple; bh=lZcEMmty7YYc4yV+0jbs+lDLlGoNtN5lfaDIS8gEpg4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KhruyGH2fidVk71p6C2K5TFMKOLNckhUIxVVRUIrpEHBkSkjPurHwpw8dTepTcaeI3Jdj32rqXMKs14HEwh59G41WcGTeGFC2djg8oXbW5/gjzK62HyPaKSZ/AqvVxTYK1HXv9om9FCJMXrQ7fSTOzQrkk3qRYz1qZ+Ph8/cAI0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=SeAud3hX; arc=none smtp.client-ip=209.85.210.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="SeAud3hX" Received: by mail-ot1-f47.google.com with SMTP id 46e09a7af769-700a6853664so1047373a34.1 for ; Sun, 23 Jun 2024 20:23:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1719199431; x=1719804231; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=3FWaEUeTMDHJoELxY+ZgcV9lMMpnHL5SsFDjxF9/VXs=; b=SeAud3hXL/2RdDm/2wUpJBK6M3s7uu9cwnvnKvHvYYCR6Yy4RqtG3kcHy4Zmd3copI uoKhf71ysYu/EZZvrnFgAKfUH8GA/HF2W5xFyOypEXoBVYS4VEeJTFBuHje/jBe3wn/G m8Wo3vR2VI5lfqZztjgtfxQUJrBuolu1kEcyH8HIXlPJjuEi993UewgOP+gPsoyTt3sq lxEacv3CuJy5tNIP4hiTZobEUZT4JTLzguJmMJEGcvNY71+v8pJ7hnvbezyyjPXeT1Ys lkiXoKo4oYXLt33qi8I8x/DEimROdL/elSiFoyO/JT/ARciMj98Yvzc4TupK4EDNtYyK g5LQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719199431; x=1719804231; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3FWaEUeTMDHJoELxY+ZgcV9lMMpnHL5SsFDjxF9/VXs=; b=AZa5NW1ElouQ6cKPqT7celo3v9z2KKoFEOhVnMoY8TNspSP76gkZzAN8r3SdM/YBxr gVlt026ylZEIeWhfKZEm5lGKRKtOXXsS3tErpgbh4cDE2I5yGlZPiCmssFYz5+dOkWxy 5gmxVOOfdDDdfMgTfQ10Et49Is9q/yP//MrcgZy7VwlyBGrW4ktgmDOisBGV3NIsmAFU EgLVBm+h3wSFg1K+1E1hg9u0Wepfa+oLOyi2wDXO2qQHLH6Ffa3NGvnvTSsoLUMMBmog HzPvbGxSKhXnGmN+5OEbW5gUAabWcWPo/YwFcf2C/fgJMteoW6sfftYHxGa/UnD51u9J n8Aw== X-Forwarded-Encrypted: i=1; AJvYcCWugUK4yrgCfMFmVn+Uk7rsnN1sFeILzbTBA8WUic9JFh519wjRDiwkijcEnzjtgxOwmLIpOOUTGQ8M7RgtEUY5lg2aDkXqhF14AkHc X-Gm-Message-State: AOJu0YyAg72+mV+RN6QKlOu8IDootCNCP4dAtGHvbV2KYhGkdYrlSiIW H3qxCKUd+1mmJrGRlo3ZilBn3wD2G4mEvZYCygoXybi9UkbKJRtJdKWoJPe5wlQ= X-Google-Smtp-Source: AGHT+IE+osSaSeirW6Qbfg0AmVximTUoIwMN39FxDLs9j+BLB3XcDNJN4I4yZNiCnV4rh4f1rTSaSg== X-Received: by 2002:a05:6830:4428:b0:6fb:9752:4d3a with SMTP id 46e09a7af769-700afa03484mr4199879a34.24.1719199430755; Sun, 23 Jun 2024 20:23:50 -0700 (PDT) Received: from ghost ([2601:647:5700:6860:e283:b00b:36c9:cbf5]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-716bb040d0esm3811211a12.79.2024.06.23.20.23.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Jun 2024 20:23:49 -0700 (PDT) Date: Sun, 23 Jun 2024 20:23:47 -0700 From: Charlie Jenkins To: Jisheng Zhang Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Ard Biesheuvel , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org Subject: Re: [PATCH v2] riscv: enable HAVE_ARCH_STACKLEAK Message-ID: References: <20240623235316.2010-1-jszhang@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240623235316.2010-1-jszhang@kernel.org> On Mon, Jun 24, 2024 at 07:53:16AM +0800, Jisheng Zhang wrote: > Add support for the stackleak feature. Whenever the kernel returns to user > space the kernel stack is filled with a poison value. > > At the same time, disables the plugin in EFI stub code because EFI stub > is out of scope for the protection. > > Tested on qemu and milkv duo: > / # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT > [ 38.675575] lkdtm: Performing direct entry STACKLEAK_ERASING > [ 38.678448] lkdtm: stackleak stack usage: > [ 38.678448] high offset: 288 bytes > [ 38.678448] current: 496 bytes > [ 38.678448] lowest: 1328 bytes > [ 38.678448] tracked: 1328 bytes > [ 38.678448] untracked: 448 bytes > [ 38.678448] poisoned: 14312 bytes > [ 38.678448] low offset: 8 bytes > [ 38.689887] lkdtm: OK: the rest of the thread stack is properly erased > > Signed-off-by: Jisheng Zhang > --- > > since v2: > - add #include to fixing compiler error found by > Charlie Thanks! Reviewed-by: Charlie Jenkins > > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/thread_info.h | 1 + > arch/riscv/kernel/entry.S | 4 ++++ > drivers/firmware/efi/libstub/Makefile | 3 ++- > 4 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 0525ee2d63c7..9cbfdffec96c 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -118,6 +118,7 @@ config RISCV > select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT > select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET > select HAVE_ARCH_SECCOMP_FILTER > + select HAVE_ARCH_STACKLEAK > select HAVE_ARCH_THREAD_STRUCT_WHITELIST > select HAVE_ARCH_TRACEHOOK > select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU > diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h > index 5d473343634b..fca5c6be2b81 100644 > --- a/arch/riscv/include/asm/thread_info.h > +++ b/arch/riscv/include/asm/thread_info.h > @@ -10,6 +10,7 @@ > > #include > #include > +#include > > /* thread information allocation */ > #define THREAD_SIZE_ORDER CONFIG_THREAD_SIZE_ORDER > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S > index 68a24cf9481a..80ff55a26d13 100644 > --- a/arch/riscv/kernel/entry.S > +++ b/arch/riscv/kernel/entry.S > @@ -130,6 +130,10 @@ SYM_CODE_START_NOALIGN(ret_from_exception) > #endif > bnez s0, 1f > > +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK > + call stackleak_erase_on_task_stack > +#endif > + > /* Save unwound kernel stack pointer in thread_info */ > addi s0, sp, PT_SIZE_ON_STACK > REG_S s0, TASK_TI_KERNEL_SP(tp) > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index 06f0428a723c..3a9521c57641 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -28,7 +28,8 @@ cflags-$(CONFIG_ARM) += -DEFI_HAVE_STRLEN -DEFI_HAVE_STRNLEN \ > -DEFI_HAVE_MEMCHR -DEFI_HAVE_STRRCHR \ > -DEFI_HAVE_STRCMP -fno-builtin -fpic \ > $(call cc-option,-mno-single-pic-base) > -cflags-$(CONFIG_RISCV) += -fpic -DNO_ALTERNATIVE -mno-relax > +cflags-$(CONFIG_RISCV) += -fpic -DNO_ALTERNATIVE -mno-relax \ > + $(DISABLE_STACKLEAK_PLUGIN) > cflags-$(CONFIG_LOONGARCH) += -fpie > > cflags-$(CONFIG_EFI_PARAMS_FROM_FDT) += -I$(srctree)/scripts/dtc/libfdt > -- > 2.43.0 >