From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7ABEEA5F; Sat, 22 Jun 2024 00:59:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719017957; cv=none; b=Q/HTJaJ5AmNp3AMNc03BhS4ahc0XBCnha7BPtBCkVzMT/lCY6t4Gu22Vch9Ze/IGdYhrto44h6fbspMIBMTui58HltXQLZ0oqwXhf/CsaAHt8MsxPTGyFlNyK7s1ethbgxCjVkFuR+wW51E0nOKKcHsTKvtbF3b88tsJDplLEYc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719017957; c=relaxed/simple; bh=FQ1S0HDz0vGglXBuV05rXrXWvmAMYzorAlIge6VS7nE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=enx6BJjFAUqP+EyfpmwpGkR925YuibQ5EwvmsJpJ06jSrwEPmPSFkZqUofdhZ0rVOnUXLfx7HwwVOOqMa7Jx2ls/gL8Xf5po7xSlYMff4FyD2raJndJ5/I5seb9UvrmlYyBwgLAmCKT/Eoj3jzJqnFyQIgyCiW2/Dt3auBAh4cs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=e6p6yNc+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="e6p6yNc+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B7ECC2BBFC; Sat, 22 Jun 2024 00:59:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719017956; bh=FQ1S0HDz0vGglXBuV05rXrXWvmAMYzorAlIge6VS7nE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e6p6yNc+6wYkOLheeXy5wx7XnlxNGY6XrTs3XFzZ11RSX/pOWaja5pXoi0pwvnqjl UBZ8Mti2dRn44UvUN6IbKwjKVl1EcdcrZRIuJDmF2uNbEIuJDCX7F8fKxqlFULHNuZ /VjBZb/gaKMZ2mANPL8NOLQXVIJ8Pxdz4s7jIez7FPVEvWfwUhpEFmkOQLqIYjRr0H UnFYkPw7qd8nh52b6hpwuBKAK2yEfdipX9QQowu0nn7sdgcXaGiAY2NUF5POlnpZtA aurDTD+pwSv7PEszXP8OVMbz+B7nPd1ZzGOCn62M4/B18FeivW2GqgNCg6l22lRy+i xn0moK+0q3hmw== Date: Sat, 22 Jun 2024 08:45:16 +0800 From: Jisheng Zhang To: Charlie Jenkins 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] riscv: enable HAVE_ARCH_STACKLEAK Message-ID: References: <20240617123029.723-1-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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Jun 21, 2024 at 03:10:42PM -0700, Charlie Jenkins wrote: > On Mon, Jun 17, 2024 at 08:30:29PM +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 > > --- > > arch/riscv/Kconfig | 1 + > > arch/riscv/kernel/entry.S | 4 ++++ > > drivers/firmware/efi/libstub/Makefile | 3 ++- > > 3 files changed, 7 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 > > When this is selected, stackleak.h include > arch/riscv/include/asm/thread_info.h without sizes.h and I hit: > > ./arch/riscv/include/asm/thread_info.h:30:33: error: ‘SZ_4K’ undeclared here (not in a function) > 30 | #define OVERFLOW_STACK_SIZE SZ_4K > | ^~~~~ > > Adding "#include " to thread_info.h resolves the issue. > I am testing this based on 6.10-rc4. Did you encounter this? I didn't meet this kind of compiler error when testing. Mind to share your .config file? It looks strange. > > - Charlie > > > select HAVE_ARCH_THREAD_STRUCT_WHITELIST > > select HAVE_ARCH_TRACEHOOK > > select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU > > 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 > > > > > > _______________________________________________ > > linux-riscv mailing list > > linux-riscv@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-riscv