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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 84A80C43603 for ; Wed, 18 Dec 2019 23:12:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56435218AC for ; Wed, 18 Dec 2019 23:12:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="cvPGswJD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726771AbfLRXMV (ORCPT ); Wed, 18 Dec 2019 18:12:21 -0500 Received: from mail-wr1-f73.google.com ([209.85.221.73]:45152 "EHLO mail-wr1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726741AbfLRXMT (ORCPT ); Wed, 18 Dec 2019 18:12:19 -0500 Received: by mail-wr1-f73.google.com with SMTP id d8so1496603wrq.12 for ; Wed, 18 Dec 2019 15:12:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=O7cRpxVyt8uxMLcyDyuXxaiEb45NcHrYdQjrFEEd8is=; b=cvPGswJDDCWWZrQ9HPqf9ZoStjXiGuTN61KVqKFRTF/ugxQS/hxj7FlWuHb/7dRR/0 Bw8AMJKfchRCkhA0FflSqoIW/fbUNTuZABELRviUTxuBYe6qdHxF/ZHNaJ1i/9h4EQhz +o/JTPG67rwkv6AoO/pTlylX9MEI0+7oQmhsNGQCvoxs3UsrO/e9ReQdV2REYnEYqxbx yrPb4MLABG4L4OQVFX+asx6Fcsk8NMZEEc1QJGhnMWuxUrtnHK5bDH58u13ocqlmGjXv mXmUY/npxI6D8qYLlsz783loophJ8C3MgwePm7yq/tfmeGrwhIm5W6NJXEPeLfZrglOA 8tag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=O7cRpxVyt8uxMLcyDyuXxaiEb45NcHrYdQjrFEEd8is=; b=J8NHnNSKe9qf6IqcMaVdFPZINIq8Snc4A0w7GkudQOPb72PwfkmsVFGLOYpOHn12JM yMk46R3h4cxvrsNKwd59o1iFfGvNeuc0m33tgtgQ0Qp6vkpBwWpF87NiXcIq2oUWE9q8 61IJNrdM7uxTqaYkjR2juoXcsx1ZMFAypMTjBg4SQLXmOcZBZj3/CNDF7kxQ6o0ps2j7 AtNrFpye0rrruPyVN03P30zvTi4tHltivke5MsrXIl/G2FCkbTsP9Wzx08vykFnYOhy2 Q9pCmRIxgE1LdOwl/DraqKtmcw6XHaHRlhrs88rZRRZND0FC+n9GgRVuYlrLu/BCOMgx aYkw== X-Gm-Message-State: APjAAAU7wUlk3jHiigcG47XLAuy3SwLYnXD57pe+0jzxXMsrWspW6fQm Z5JbVkhYIyuiox4qYjs2PwgWGP2udw== X-Google-Smtp-Source: APXvYqzBhqL5t5GVHOOnngl6Ggq6tOVXgSxy+M5wrhtKJpCIzIHJeM453iRTXK5dgJeLZdE7REmZ1UTtJg== X-Received: by 2002:adf:81c2:: with SMTP id 60mr5454204wra.8.1576710735282; Wed, 18 Dec 2019 15:12:15 -0800 (PST) Date: Thu, 19 Dec 2019 00:11:49 +0100 In-Reply-To: <20191218231150.12139-1-jannh@google.com> Message-Id: <20191218231150.12139-3-jannh@google.com> Mime-Version: 1.0 References: <20191218231150.12139-1-jannh@google.com> X-Mailer: git-send-email 2.24.1.735.g03f4e72817-goog Subject: [PATCH v7 3/4] x86/dumpstack: Introduce die_addr() for die() with #GP fault address From: Jann Horn To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , kasan-dev@googlegroups.com, jannh@google.com Cc: linux-kernel@vger.kernel.org, Andrey Konovalov , Andy Lutomirski , Sean Christopherson Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Split __die() into __die_header() and __die_body(). This allows inserting extra information below the header line that initiates the bug report. Introduce a new function die_addr() that behaves like die(), but is for faults only and uses __die_header()+__die_body() so that a future commit can print extra information after the header line. Signed-off-by: Jann Horn --- Notes: v3: new patch v4-v6: no changes v7: - introduce die_addr() instead of open-coding __die_header() and __die_body() calls in traps.c (Borislav) - make __die_header() and __die_body() static - rewrite commit message arch/x86/include/asm/kdebug.h | 1 + arch/x86/kernel/dumpstack.c | 24 +++++++++++++++++++++++- arch/x86/kernel/traps.c | 5 ++++- 3 files changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h index 75f1e35e7c15..247ab14c6309 100644 --- a/arch/x86/include/asm/kdebug.h +++ b/arch/x86/include/asm/kdebug.h @@ -33,6 +33,7 @@ enum show_regs_mode { }; extern void die(const char *, struct pt_regs *,long); +void die_addr(const char *str, struct pt_regs *regs, long err, long gp_addr); extern int __must_check __die(const char *, struct pt_regs *, long); extern void show_stack_regs(struct pt_regs *regs); extern void __show_regs(struct pt_regs *regs, enum show_regs_mode); diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index e07424e19274..8995bf10c97c 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -365,7 +365,7 @@ void oops_end(unsigned long flags, struct pt_regs *regs, int signr) } NOKPROBE_SYMBOL(oops_end); -int __die(const char *str, struct pt_regs *regs, long err) +static void __die_header(const char *str, struct pt_regs *regs, long err) { const char *pr = ""; @@ -384,7 +384,11 @@ int __die(const char *str, struct pt_regs *regs, long err) IS_ENABLED(CONFIG_KASAN) ? " KASAN" : "", IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION) ? (boot_cpu_has(X86_FEATURE_PTI) ? " PTI" : " NOPTI") : ""); +} +NOKPROBE_SYMBOL(__die_header); +static int __die_body(const char *str, struct pt_regs *regs, long err) +{ show_regs(regs); print_modules(); @@ -394,6 +398,13 @@ int __die(const char *str, struct pt_regs *regs, long err) return 0; } +NOKPROBE_SYMBOL(__die_body); + +int __die(const char *str, struct pt_regs *regs, long err) +{ + __die_header(str, regs, err); + return __die_body(str, regs, err); +} NOKPROBE_SYMBOL(__die); /* @@ -410,6 +421,17 @@ void die(const char *str, struct pt_regs *regs, long err) oops_end(flags, regs, sig); } +void die_addr(const char *str, struct pt_regs *regs, long err, long gp_addr) +{ + unsigned long flags = oops_begin(); + int sig = SIGSEGV; + + __die_header(str, regs, err); + if (__die_body(str, regs, err)) + sig = 0; + oops_end(flags, regs, sig); +} + void show_regs(struct pt_regs *regs) { show_regs_print_info(KERN_DEFAULT); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index c8b4ae6aed5b..4c691bb9e0d9 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -621,7 +621,10 @@ do_general_protection(struct pt_regs *regs, long error_code) "maybe for address", gp_addr); - die(desc, regs, error_code); + if (hint != GP_NON_CANONICAL) + gp_addr = 0; + + die_addr(desc, regs, error_code, gp_addr); return; } -- 2.24.1.735.g03f4e72817-goog