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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 B5C63C43461 for ; Tue, 11 May 2021 00:39:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9310261629 for ; Tue, 11 May 2021 00:39:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230188AbhEKAkE (ORCPT ); Mon, 10 May 2021 20:40:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230097AbhEKAj4 (ORCPT ); Mon, 10 May 2021 20:39:56 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFCECC061761 for ; Mon, 10 May 2021 17:38:50 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id b3so9964715plg.11 for ; Mon, 10 May 2021 17:38:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZbspQKLdATEoVgdZs/IrxjMWjbvi9Biurj+hlH6bsBM=; b=l01jwAL99b+6ual1hc61NJSWCegcP0OTWeWfMKVptRHwlPhBzQatsTfYxNLyzCKCI9 pfUZGOYVjGcFG7VhsQY2uwAlaFlLMaUNEkWSQS3DbHJa1TkLydThseReY29dsCedVMbP FQtqrBr3pbjlnjgB0MM/wRMAsvDnDu1VFvAAc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZbspQKLdATEoVgdZs/IrxjMWjbvi9Biurj+hlH6bsBM=; b=as7ZIKSbiX32TVxLIReiXeSmALN73gRVfJT4f38KE6TQnn+uwhfMn/vR7ihxebUl6s MbWtBFFEhS+fY/35gkA+84hNZ3oWhrKG0kamtzNlSAl441ZT/HvzLJmsBvttipkWNMw1 TTxA/HMtTGp0e74Ag5Fm7X6gIPBcWb7X5UgACasDusUmPeiL543EadtHq5Rmsc2jQMGS hMirSIG3fyu7O8oFvir5wgyRLzKGm20UMdH77KI0sUIfQ1CD+PRBkrAIJmR70gYgYgo2 1Wd45IGWKjg3KOPAph+vakliK0MsW8Ml1WXhvH7CFGRoKUOrwzsytPBIxzgUchMRbjQE P4IA== X-Gm-Message-State: AOAM532svIxyxDYOu6hbSz5ylFjabpj4PjJhSn5CB1XZgzaYpa49Ypui N8MK8UGBAzDXCXjWiwYqkyqRWw== X-Google-Smtp-Source: ABdhPJwSUYof8wAYTnuWBV3+i1jYXR/kYrapu8CcdXl3Q9yecO3TXFdmi4MCtvpnoE3YO2RKxgRWJg== X-Received: by 2002:a17:902:8a86:b029:ef:5161:99e7 with SMTP id p6-20020a1709028a86b02900ef516199e7mr2141266plo.32.1620693530310; Mon, 10 May 2021 17:38:50 -0700 (PDT) Received: from smtp.gmail.com ([2620:15c:202:201:6765:417e:19fc:9756]) by smtp.gmail.com with ESMTPSA id d26sm12142539pfq.215.2021.05.10.17.38.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 10 May 2021 17:38:50 -0700 (PDT) From: Stephen Boyd To: Andrew Morton , Petr Mladek Cc: linux-kernel@vger.kernel.org, Jiri Olsa , Alexei Starovoitov , Jessica Yu , Evan Green , Hsin-Yi Wang Subject: [PATCH v6 02/13] buildid: Add API to parse build ID out of buffer Date: Mon, 10 May 2021 17:38:34 -0700 Message-Id: <20210511003845.2429846-3-swboyd@chromium.org> X-Mailer: git-send-email 2.31.1.607.g51e8a6a459-goog In-Reply-To: <20210511003845.2429846-1-swboyd@chromium.org> References: <20210511003845.2429846-1-swboyd@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add an API that can parse the build ID out of a buffer, instead of a vma, to support printing a kernel module's build ID for stack traces. Cc: Jiri Olsa Cc: Alexei Starovoitov Cc: Jessica Yu Cc: Evan Green Cc: Hsin-Yi Wang Signed-off-by: Stephen Boyd --- include/linux/buildid.h | 1 + lib/buildid.c | 50 ++++++++++++++++++++++++++++++----------- 2 files changed, 38 insertions(+), 13 deletions(-) diff --git a/include/linux/buildid.h b/include/linux/buildid.h index 40232f90db6e..ebce93f26d06 100644 --- a/include/linux/buildid.h +++ b/include/linux/buildid.h @@ -8,5 +8,6 @@ int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id, __u32 *size); +int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size); #endif diff --git a/lib/buildid.c b/lib/buildid.c index e014636ec3eb..6aea1c4e5e85 100644 --- a/lib/buildid.c +++ b/lib/buildid.c @@ -2,30 +2,23 @@ #include #include +#include #include #define BUILD_ID 3 + /* * Parse build id from the note segment. This logic can be shared between * 32-bit and 64-bit system, because Elf32_Nhdr and Elf64_Nhdr are * identical. */ -static inline int parse_build_id(void *page_addr, - unsigned char *build_id, - __u32 *size, - void *note_start, - Elf32_Word note_size) +static int parse_build_id_buf(unsigned char *build_id, + __u32 *size, + const void *note_start, + Elf32_Word note_size) { Elf32_Word note_offs = 0, new_offs; - /* check for overflow */ - if (note_start < page_addr || note_start + note_size < note_start) - return -EINVAL; - - /* only supports note that fits in the first page */ - if (note_start + note_size > page_addr + PAGE_SIZE) - return -EINVAL; - while (note_offs + sizeof(Elf32_Nhdr) < note_size) { Elf32_Nhdr *nhdr = (Elf32_Nhdr *)(note_start + note_offs); @@ -50,9 +43,27 @@ static inline int parse_build_id(void *page_addr, break; note_offs = new_offs; } + return -EINVAL; } +static inline int parse_build_id(void *page_addr, + unsigned char *build_id, + __u32 *size, + void *note_start, + Elf32_Word note_size) +{ + /* check for overflow */ + if (note_start < page_addr || note_start + note_size < note_start) + return -EINVAL; + + /* only supports note that fits in the first page */ + if (note_start + note_size > page_addr + PAGE_SIZE) + return -EINVAL; + + return parse_build_id_buf(build_id, size, note_start, note_size); +} + /* Parse build ID from 32-bit ELF */ static int get_build_id_32(void *page_addr, unsigned char *build_id, __u32 *size) @@ -148,3 +159,16 @@ int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id, put_page(page); return ret; } + +/** + * build_id_parse_buf - Get build ID from a buffer + * @buf: Elf note section(s) to parse + * @buf_size: Size of @buf in bytes + * @build_id: Build ID parsed from @buf, at least BUILD_ID_SIZE_MAX long + * + * Return: 0 on success, -EINVAL otherwise + */ +int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size) +{ + return parse_build_id_buf(build_id, NULL, buf, buf_size); +} -- https://chromeos.dev