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 X-Spam-Level: X-Spam-Status: No, score=-24.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07B80C432C3 for ; Mon, 8 Feb 2021 18:06:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D221B64DE1 for ; Mon, 8 Feb 2021 18:06:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235424AbhBHSGC (ORCPT ); Mon, 8 Feb 2021 13:06:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:47962 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235096AbhBHSC2 (ORCPT ); Mon, 8 Feb 2021 13:02:28 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 66D7664ED7; Mon, 8 Feb 2021 17:58:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612807134; bh=FydyvUabgfSj0tpi0vAQQgW4003YdZy9X1JeOpqxO58=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iPuvdzXP2Vn5XNTW4YPEjBZ+Gw/1yMSjOqVY/Wok9wBodGCFW60EHz/4qN0G7Be4A kjcYbnIzdq9OpGUaiGUR8hZiXUGyrbni24YjNH0IKuSaceqj1XEDnTOF2LY7/rjV7s hS+JdRz5Ms2rEklJdHlldX7r3l5y3Gfj5wWX3LpBn2smpfl17OIY/RSPX+IbRI6TLR VgmZTXzP5zyAW2DOc1vk85ds/hT/Rx87JvMigQ0gRdwuMKEh4IoMLCpmuw2EHqq3R7 2/P6MEivyVZsa0xWpjh241o/ZmcLUI1n/L4mtOLasR+3aosyDPVCddtwtBpIQc68DS eaDNEwK5eD3Ew== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nathan Chancellor , Kees Cook , Nick Desaulniers , Andrew Morton , Linus Torvalds , Sasha Levin , clang-built-linux@googlegroups.com Subject: [PATCH AUTOSEL 5.10 34/36] ubsan: implement __ubsan_handle_alignment_assumption Date: Mon, 8 Feb 2021 12:58:04 -0500 Message-Id: <20210208175806.2091668-34-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210208175806.2091668-1-sashal@kernel.org> References: <20210208175806.2091668-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Nathan Chancellor [ Upstream commit 28abcc963149e06d956d95a18a85f4ba26af746f ] When building ARCH=mips 32r2el_defconfig with CONFIG_UBSAN_ALIGNMENT: ld.lld: error: undefined symbol: __ubsan_handle_alignment_assumption referenced by slab.h:557 (include/linux/slab.h:557) main.o:(do_initcalls) in archive init/built-in.a referenced by slab.h:448 (include/linux/slab.h:448) do_mounts_rd.o:(rd_load_image) in archive init/built-in.a referenced by slab.h:448 (include/linux/slab.h:448) do_mounts_rd.o:(identify_ramdisk_image) in archive init/built-in.a referenced 1579 more times Implement this for the kernel based on LLVM's handleAlignmentAssumptionImpl because the kernel is not linked against the compiler runtime. Link: https://github.com/ClangBuiltLinux/linux/issues/1245 Link: https://github.com/llvm/llvm-project/blob/llvmorg-11.0.1/compiler-rt/lib/ubsan/ubsan_handlers.cpp#L151-L190 Link: https://lkml.kernel.org/r/20210127224451.2587372-1-nathan@kernel.org Signed-off-by: Nathan Chancellor Acked-by: Kees Cook Reviewed-by: Nick Desaulniers Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- lib/ubsan.c | 31 +++++++++++++++++++++++++++++++ lib/ubsan.h | 6 ++++++ 2 files changed, 37 insertions(+) diff --git a/lib/ubsan.c b/lib/ubsan.c index cb9af3f6b77e3..adf8dcf3c84e6 100644 --- a/lib/ubsan.c +++ b/lib/ubsan.c @@ -427,3 +427,34 @@ void __ubsan_handle_load_invalid_value(void *_data, void *val) ubsan_epilogue(); } EXPORT_SYMBOL(__ubsan_handle_load_invalid_value); + +void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr, + unsigned long align, + unsigned long offset); +void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr, + unsigned long align, + unsigned long offset) +{ + struct alignment_assumption_data *data = _data; + unsigned long real_ptr; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, "alignment-assumption"); + + if (offset) + pr_err("assumption of %lu byte alignment (with offset of %lu byte) for pointer of type %s failed", + align, offset, data->type->type_name); + else + pr_err("assumption of %lu byte alignment for pointer of type %s failed", + align, data->type->type_name); + + real_ptr = ptr - offset; + pr_err("%saddress is %lu aligned, misalignment offset is %lu bytes", + offset ? "offset " : "", BIT(real_ptr ? __ffs(real_ptr) : 0), + real_ptr & (align - 1)); + + ubsan_epilogue(); +} +EXPORT_SYMBOL(__ubsan_handle_alignment_assumption); diff --git a/lib/ubsan.h b/lib/ubsan.h index 7b56c09473a98..9a0b71c5ff9fb 100644 --- a/lib/ubsan.h +++ b/lib/ubsan.h @@ -78,6 +78,12 @@ struct invalid_value_data { struct type_descriptor *type; }; +struct alignment_assumption_data { + struct source_location location; + struct source_location assumption_location; + struct type_descriptor *type; +}; + #if defined(CONFIG_ARCH_SUPPORTS_INT128) typedef __int128 s_max; typedef unsigned __int128 u_max; -- 2.27.0