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=-0.7 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 5B5C4C0044C for ; Wed, 7 Nov 2018 18:58:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A44C20862 for ; Wed, 7 Nov 2018 18:58:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A44C20862 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729937AbeKHE3o (ORCPT ); Wed, 7 Nov 2018 23:29:44 -0500 Received: from mail-io1-f71.google.com ([209.85.166.71]:44289 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726335AbeKHE3o (ORCPT ); Wed, 7 Nov 2018 23:29:44 -0500 Received: by mail-io1-f71.google.com with SMTP id u5-v6so19950189iol.11 for ; Wed, 07 Nov 2018 10:58:04 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=3dp5mjuZq6EaeSi9osdN2HZdPlrZMq2hPbZhmyc9ctM=; b=OiypiqdFY5JHTlw8q7jLjmWFDwwORqh3ItIpDMecSQdLvp3YuIqfd8a2SBmmrbb08T bj8nLLsedJZ+v6CV0T+SysWym0IGgg7Jw+fjRHFF+ZZc7O51wbl3Zcg8dtZgzSjSYGXP OqyrjXVyePmvJ75Mb6NVlrbd7JZmnfGrQzdwVWjz7lZNXdNTihQYoH5MJoasszfdZHAk OT1+qG2mw6Q7+kvh8OMvTK79p/Y+wNDuk/w/vXMLNw00Q3hIre5UvWSriIMveqKOGUXv pLD6hqdcdLv4UExC2so8H+FWvW/ZHNWqeMqjJhl+iDTYeCTKocqP+PX9n0NH0zawrUtQ vbZQ== X-Gm-Message-State: AGRZ1gLdpsS6jTTjT+YKU1xQoQmsBW1HQJKI5IttEb4RS6NLZDez8JPn aoEPy8BKkmHWBTTbYzXDOhrkrtwe1RY3npMvmVmkyKPJkWIR X-Google-Smtp-Source: AJdET5dIG4oTu1JwxtjFRWcd16E5FGhLCPvDJhvhsuhUICCXXm5MyuhmoeU6IFJm4EiVDtzsxImI0pBGWiwr5zu2sVeizIU6nMPN MIME-Version: 1.0 X-Received: by 2002:a24:2c91:: with SMTP id i139-v6mr1060561iti.40.1541617084335; Wed, 07 Nov 2018 10:58:04 -0800 (PST) Date: Wed, 07 Nov 2018 10:58:04 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000b10cfe057a17b246@google.com> Subject: KMSAN: kernel-infoleak in kvm_write_guest_page From: syzbot To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, rkrcmar@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 7438a3b20295 kmsan: print user address when reporting info.. git tree: https://github.com/google/kmsan.git/master console output: https://syzkaller.appspot.com/x/log.txt?x=10d782f5400000 kernel config: https://syzkaller.appspot.com/x/.config?x=8df5fc509a1b351b dashboard link: https://syzkaller.appspot.com/bug?extid=a8ef68d71211ba264f56 compiler: clang version 8.0.0 (trunk 343298) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15f09133400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a39e05400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+a8ef68d71211ba264f56@syzkaller.appspotmail.com L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html for details. ================================================================== BUG: KMSAN: kernel-infoleak in __copy_to_user include/linux/uaccess.h:121 [inline] BUG: KMSAN: kernel-infoleak in __kvm_write_guest_page arch/x86/kvm/../../../virt/kvm/kvm_main.c:1849 [inline] BUG: KMSAN: kernel-infoleak in kvm_write_guest_page+0x373/0x500 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1861 CPU: 1 PID: 6274 Comm: syz-executor149 Not tainted 4.19.0+ #78 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x32d/0x480 lib/dump_stack.c:113 kmsan_report+0x19f/0x300 mm/kmsan/kmsan.c:911 kmsan_internal_check_memory+0x35f/0x450 mm/kmsan/kmsan.c:993 kmsan_copy_to_user+0x7c/0xe0 mm/kmsan/kmsan_hooks.c:552 __copy_to_user include/linux/uaccess.h:121 [inline] __kvm_write_guest_page arch/x86/kvm/../../../virt/kvm/kvm_main.c:1849 [inline] kvm_write_guest_page+0x373/0x500 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1861 kvm_write_guest+0x1e1/0x360 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1883 kvm_pv_clock_pairing arch/x86/kvm/x86.c:6793 [inline] kvm_emulate_hypercall+0x1c96/0x21b0 arch/x86/kvm/x86.c:6866 handle_vmcall+0x41/0x50 arch/x86/kvm/vmx.c:7487 vmx_handle_exit+0x1e81/0xbac0 arch/x86/kvm/vmx.c:10128 vcpu_enter_guest arch/x86/kvm/x86.c:7667 [inline] vcpu_run arch/x86/kvm/x86.c:7730 [inline] kvm_arch_vcpu_ioctl_run+0xac32/0x11d80 arch/x86/kvm/x86.c:7930 kvm_vcpu_ioctl+0xfb1/0x1f90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2590 do_vfs_ioctl+0xf77/0x2d30 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:702 [inline] __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:707 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:707 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x442b39 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 1b 0c fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcb4e05478 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000442b39 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000007 RBP: 00000000006cd018 R08: 0000000020000100 R09: 0000000020000100 R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000403be0 R13: 0000000000403c70 R14: 0000000000000000 R15: 0000000000000000 Local variable description: ----clock_pairing.i@kvm_emulate_hypercall Variable was created at: kvm_emulate_hypercall+0x60/0x21b0 arch/x86/kvm/x86.c:6827 handle_vmcall+0x41/0x50 arch/x86/kvm/vmx.c:7487 Bytes 28-63 of 64 are uninitialized Memory access of size 64 starts at ffff8801aac5f3d8 Data copied to user address 0000000020000000 ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches