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=-18.8 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, 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 3B017C433B4 for ; Sat, 10 Apr 2021 01:53:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12EF161243 for ; Sat, 10 Apr 2021 01:53:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234079AbhDJBxV (ORCPT ); Fri, 9 Apr 2021 21:53:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36040 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233915AbhDJBxR (ORCPT ); Fri, 9 Apr 2021 21:53:17 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFD84C061762 for ; Fri, 9 Apr 2021 18:53:03 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id j7so3596704plx.2 for ; Fri, 09 Apr 2021 18:53:03 -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=DGFh3qWgLs0t89nbGjs6WV20bw9jUEh3AtOwrVlN15v3BXK+HEMfTFk0uhyoXu9NOw A0e4FPEIug7eafeH2QF0kzDE+gHgefI/9FlViF7KKbqeu2cPyp5Q7dT7o3BEee4H+1zJ WSj64z8O0SFFz2c5fUDNHZ0uo70hbSGfQSK2s= 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=bOnigjIbYoyUMCq3Cm69EEADVP0xm7Xkk0QBer+7X76bGkpK+NJFoi071jM2JLonu+ XSN48DKxDXBLxsCBBgHep5Qi8t8lv2ODlfn68RmaRw80B2vKGEAIc6gYQDeejULLlVZO 2aKAqY3t5EVXhgiSZzI43/59TIxm4ZlQMdxrXOVj48qqZ9Zyif1iDyC4s/aZCXdfvoy5 vS0T34fzWr3HFogbyVX6yEfINaRUPinY4rW73eLZo7mm8jAHXslpWs7/8d/PIav5UhJe D4gyIykljXuJQron8QaDvpwPQcdG79MDJIxP/PBhw7uM3nFwZgLq2R/9aOloSmO+S5EX dbmQ== X-Gm-Message-State: AOAM533yRKmhFdFIYpd4YQMLN6Gu+vx5PQbLcpQEn2jMw8sU7V0YMFFP BfK8sB/Hzu3LXG0vIMKcfBldrQ== X-Google-Smtp-Source: ABdhPJw3MdU2sdVtt5oqVkKq/I/KEJ5me4jxlg54Haubzowlib3r6LiBp3NXWncRHuPglDoa2ydONw== X-Received: by 2002:a17:90a:6b08:: with SMTP id v8mr15813867pjj.131.1618019583573; Fri, 09 Apr 2021 18:53:03 -0700 (PDT) Received: from smtp.gmail.com ([2620:15c:202:201:5141:7881:7013:743b]) by smtp.gmail.com with ESMTPSA id n23sm3837962pgl.49.2021.04.09.18.53.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Apr 2021 18:53:03 -0700 (PDT) From: Stephen Boyd To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Jiri Olsa , Alexei Starovoitov , Jessica Yu , Evan Green , Hsin-Yi Wang Subject: [PATCH v4 02/13] buildid: Add API to parse build ID out of buffer Date: Fri, 9 Apr 2021 18:52:49 -0700 Message-Id: <20210410015300.3764485-3-swboyd@chromium.org> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog In-Reply-To: <20210410015300.3764485-1-swboyd@chromium.org> References: <20210410015300.3764485-1-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