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=-5.7 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, 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 8DCB3ECDE4B for ; Thu, 8 Nov 2018 16:48:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 589402077B for ; Thu, 8 Nov 2018 16:48:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 589402077B 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 S1727128AbeKICY1 (ORCPT ); Thu, 8 Nov 2018 21:24:27 -0500 Received: from mail-it1-f200.google.com ([209.85.166.200]:40903 "EHLO mail-it1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726421AbeKICY0 (ORCPT ); Thu, 8 Nov 2018 21:24:26 -0500 Received: by mail-it1-f200.google.com with SMTP id y144-v6so1847616itc.5 for ; Thu, 08 Nov 2018 08:48:06 -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:in-reply-to:message-id:subject :from:to:cc; bh=m6RNL8XXq7qDZOmMDnO4GwdPzC98k7SoLoP6Zz+uK3w=; b=aoSii+YLEglbnTMYvzyyK1W6i3S6hk/L4Jjv/FLBr9MhIa6t1a9jf5A1PNYWpO/RP+ C++I5jB0kpGSJBgxeH+e1JSiwn5mGb2ZCayZNUksUyrpX2kDl1hgH5tZqTKro0EzDzid JBc1qwerHyB8qAUPMgr3nvMUUaFa2N0i6WwnFCRqdxE5cEieuwkMQRboF0mQVUO3Zfzn R2VIkWBugP6ii8NQXbO3uJhPZ/dXb0o195lMrLv1kZlSX7Hi6EBwmVoTUNdfr4O8DSCx UT/Lca74tI8g8ntRGP0UJXkLSifOd59ikhWLP0vGWzZnL9qWKy72jh+hPlbYXVkhXBwU QDOw== X-Gm-Message-State: AGRZ1gJv1ihuI17puzlliKrf3gHWMS23vAdNIAzelR4uKsGkFoFifnCG KYXu3Ou9EL9QP9RIxTwsZyKJWoR/ywv5oxsCP9gkY9uNWUmV X-Google-Smtp-Source: AJdET5capwC/ITKBO/74n5+35qXu8Z6Ps+mcdKXUyQKYgore8Okkfxh434yB0tZloFICLuzI9vJq7cWNuNOwydjA0UljrwHU+Nmi MIME-Version: 1.0 X-Received: by 2002:a24:2793:: with SMTP id g141-v6mr1472610ita.39.1541695685980; Thu, 08 Nov 2018 08:48:05 -0800 (PST) Date: Thu, 08 Nov 2018 08:48:05 -0800 In-Reply-To: X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000b6f7c3057a29ffb1@google.com> Subject: Re: Re: KMSAN: uninit-value in vcs_read From: syzbot To: Dmitry Vyukov Cc: dvyukov@google.com, glider@google.com, gregkh@linuxfoundation.org, jslaby@suse.com, kstewart@linuxfoundation.org, linux-kernel@vger.kernel.org, pombredanne@nexb.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, viro@zeniv.linux.org.uk 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 > On Tue, May 15, 2018 at 9:26 AM, syzbot > wrote: >> Hello, >> syzbot found the following crash on: >> HEAD commit: e2ab7e8abba4 kmsan: temporarily disable >> visitAsmInstructio.. >> git tree: https://github.com/google/kmsan.git/master >> console output: https://syzkaller.appspot.com/x/log.txt?x=158135db800000 >> kernel config: >> https://syzkaller.appspot.com/x/.config?x=5bf8b7964e37a698 >> dashboard link: >> https://syzkaller.appspot.com/bug?extid=fed4435f163beccc67eb >> compiler: clang version 7.0.0 (trunk 329391) >> syzkaller >> repro:https://syzkaller.appspot.com/x/repro.syz?x=17a2f91b800000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17bd452b800000 >> IMPORTANT: if you fix the bug, please add the following tag to the >> commit: >> Reported-by: syzbot+fed4435f163beccc67eb@syzkaller.appspotmail.com > #syz dup: KMSAN: kernel-infoleak in vcs_read Can't dup bug to a bug in different reporting (upstream->moderation).Please dup syzbot bugs only onto syzbot bugs for the same kernel/reporting. >> ================================================================== >> BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 >> [inline] >> BUG: KMSAN: uninit-value in vcs_read+0x18ba/0x1cc0 >> drivers/tty/vt/vc_screen.c:352 >> CPU: 1 PID: 3501 Comm: syzkaller315412 Not tainted 4.16.0+ #82 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> Google 01/01/2011 >> Call Trace: >> __dump_stack lib/dump_stack.c:17 [inline] >> dump_stack+0x185/0x1d0 lib/dump_stack.c:53 >> kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 >> kmsan_internal_check_memory+0x125/0x1d0 mm/kmsan/kmsan.c:1157 >> kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199 >> copy_to_user include/linux/uaccess.h:184 [inline] >> vcs_read+0x18ba/0x1cc0 drivers/tty/vt/vc_screen.c:352 >> __vfs_read+0x19f/0x8e0 fs/read_write.c:411 >> vfs_read+0x36c/0x6c0 fs/read_write.c:447 >> SYSC_pread64+0x275/0x310 fs/read_write.c:611 >> SyS_pread64+0x65/0x90 fs/read_write.c:598 >> do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 >> entry_SYSCALL_64_after_hwframe+0x3d/0xa2 >> RIP: 0033:0x443d39 >> RSP: 002b:00007ffcbd3c35f8 EFLAGS: 00000213 ORIG_RAX: 0000000000000011 >> RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000443d39 >> RDX: 0000000000000083 RSI: 0000000020000140 RDI: 0000000000000003 >> RBP: 00000000006ce018 R08: 00000000004002e0 R09: 00000000004002e0 >> R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004019e0 >> R13: 0000000000401a70 R14: 0000000000000000 R15: 0000000000000000 >> Uninit was stored to memory at: >> kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] >> kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] >> kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 >> __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521 >> vcs_read+0xd01/0x1cc0 drivers/tty/vt/vc_screen.c:274 >> __vfs_read+0x19f/0x8e0 fs/read_write.c:411 >> vfs_read+0x36c/0x6c0 fs/read_write.c:447 >> SYSC_pread64+0x275/0x310 fs/read_write.c:611 >> SyS_pread64+0x65/0x90 fs/read_write.c:598 >> do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 >> entry_SYSCALL_64_after_hwframe+0x3d/0xa2 >> Uninit was created at: >> kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] >> kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 >> kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 >> __kmalloc+0x23c/0x350 mm/slub.c:3791 >> kmalloc include/linux/slab.h:517 [inline] >> vc_allocate+0x438/0x800 drivers/tty/vt/vt.c:787 >> con_install+0x8c/0x640 drivers/tty/vt/vt.c:2876 >> tty_driver_install_tty drivers/tty/tty_io.c:1224 [inline] >> tty_init_dev+0x1b0/0x1020 drivers/tty/tty_io.c:1324 >> tty_open_by_driver drivers/tty/tty_io.c:1959 [inline] >> tty_open+0x15e9/0x2ea0 drivers/tty/tty_io.c:2007 >> chrdev_open+0xc20/0xd90 fs/char_dev.c:417 >> do_dentry_open+0xcc6/0x1430 fs/open.c:752 >> vfs_open+0x1b7/0x2e0 fs/open.c:866 >> do_last fs/namei.c:3379 [inline] >> path_openat+0x460a/0x6520 fs/namei.c:3520 >> do_filp_open+0x261/0x640 fs/namei.c:3554 >> do_sys_open+0x624/0x960 fs/open.c:1059 >> SYSC_open+0xab/0xc0 fs/open.c:1077 >> SyS_open+0x54/0x80 fs/open.c:1072 >> do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 >> entry_SYSCALL_64_after_hwframe+0x3d/0xa2 >> Bytes 0-79 of 131 are uninitialized >> ================================================================== >> --- >> 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 >> -- >> You received this message because you are subscribed to the Google Groups >> "syzkaller-bugs" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to syzkaller-bugs+unsubscribe@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/syzkaller-bugs/000000000000da269e056c410efd%40google.com. >> For more options, visit https://groups.google.com/d/optout.