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=2.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, UNWANTED_LANGUAGE_BODY 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 E6D77C433F5 for ; Fri, 7 Sep 2018 21:24:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8614720645 for ; Fri, 7 Sep 2018 21:24:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8614720645 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 S1728732AbeIHCGx (ORCPT ); Fri, 7 Sep 2018 22:06:53 -0400 Received: from mail-io1-f71.google.com ([209.85.166.71]:57033 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727760AbeIHCGw (ORCPT ); Fri, 7 Sep 2018 22:06:52 -0400 Received: by mail-io1-f71.google.com with SMTP id o18-v6so533373ioh.23 for ; Fri, 07 Sep 2018 14:24:03 -0700 (PDT) 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; bh=KgkqmRnS3AZzB3QIggzwrYdCYIF9GfsHtsr+USeiCIM=; b=TAxjky7fgUhO0nPg9RJwn1TDjHElnnwac2Rajfjw1ol3UpP6BsHqngz5aVYHKv6NKw PO4B4Wty4MpUXyd0Nnb0B1UQmUR/ggQzGYr/3sikbjYn4WU6mkabI2MFEiICanzhdkRx 7QUcwpFhWkhklE26DVBM9ZRbtQLO8Rher/5TEOLcwGa3PLH4AdZPaLWC3Ue3mIH0o7/H bm2LCb7jWoAumi1C5Sd4AFSH8rzEyAH07YrvdkmhniBirQJzCnIw1iy2KegSki0KdVCH zC0Qy7NcEXF1ayHjgdOvY0oo6Mq/lHVnzpOBTD7s4Fvil6SOO6sMOJCbYTqHW67A9B5W ZlBg== X-Gm-Message-State: APzg51Adv9ST16SFnE0HZYmywxZl+g8CZN8DREumXifL7AVoZjxk/u9f n+Sj7aKZHymaOxuRrsbZJKjXQZgpilb3iiJJUN3h9b4AxKYA X-Google-Smtp-Source: ANB0VdbDzDJ94OErMdVSzETOm9jOw6rmM2xpBJy0C+5Cow7u/T2qyTfVLIdpL0UBfX2NKEj53cI+Krnt00ctFt6km1Y3daobLnh7 MIME-Version: 1.0 X-Received: by 2002:a5e:d908:: with SMTP id n8-v6mr8278316iop.77.1536355443119; Fri, 07 Sep 2018 14:24:03 -0700 (PDT) Date: Fri, 07 Sep 2018 14:24:03 -0700 In-Reply-To: <000000000000038dab0575476b73@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000006fa12a05754ea030@google.com> Subject: Re: WARNING: kmalloc bug in str_read From: syzbot To: eparis@parisplace.org, linux-kernel@vger.kernel.org, paul@paul-moore.com, penguin-kernel@I-love.SAKURA.ne.jp, peter.enderborg@sony.com, sds@tycho.nsa.gov, selinux@tycho.nsa.gov, 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 syzbot has found a reproducer for the following crash on: HEAD commit: a49a9dcce802 Merge tag 'drm-fixes-2018-09-07' of git://ano.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11981149400000 kernel config: https://syzkaller.appspot.com/x/.config?x=6c9564cd177daf0c dashboard link: https://syzkaller.appspot.com/bug?extid=ac488b9811036cea7ea0 compiler: gcc (GCC) 8.0.1 20180413 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1717dfa9400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13c1adea400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+ac488b9811036cea7ea0@syzkaller.appspotmail.com random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) audit: type=1400 audit(1536355256.676:7): avc: denied { map } for pid=4365 comm="syz-executor462" path="/root/syz-executor462675731" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 WARNING: CPU: 0 PID: 4365 at mm/slab_common.c:1031 kmalloc_slab+0x56/0x70 mm/slab_common.c:1031 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 4365 Comm: syz-executor462 Not tainted 4.19.0-rc2+ #5 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+0x1c9/0x2b4 lib/dump_stack.c:113 panic+0x238/0x4e7 kernel/panic.c:184 __warn.cold.8+0x163/0x1ba kernel/panic.c:536 report_bug+0x252/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993 RIP: 0010:kmalloc_slab+0x56/0x70 mm/slab_common.c:1031 Code: c5 40 db f2 87 5d c3 b8 10 00 00 00 48 85 ff 74 f4 83 ef 01 c1 ef 03 0f b6 87 60 da f2 87 eb d8 31 c0 81 e6 00 02 00 00 75 db <0f> 0b 5d c3 48 8b 04 c5 80 da f2 87 5d c3 66 90 66 2e 0f 1f 84 00 RSP: 0018:ffff8801c2317298 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 000000000d7fffd6 RCX: ffffffff832e9d2e RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000d7fffd7 RBP: ffff8801c2317298 R08: ffff8801c197a700 R09: ffffed003b6046de R10: ffffed003b6046de R11: ffff8801db0236f3 R12: 00000000006000c0 R13: ffff8801c2317938 R14: ffff8801c23173c0 R15: 00000000006000c0 __do_kmalloc mm/slab.c:3713 [inline] __kmalloc+0x25/0x720 mm/slab.c:3727 kmalloc include/linux/slab.h:518 [inline] str_read+0x48/0x160 security/selinux/ss/policydb.c:1104 common_read+0x37c/0x560 security/selinux/ss/policydb.c:1177 policydb_read+0xf09/0x5f90 security/selinux/ss/policydb.c:2407 security_load_policy+0x23b/0x1650 security/selinux/ss/services.c:2165 sel_write_load+0x247/0x460 security/selinux/selinuxfs.c:565 __vfs_write+0x117/0x9d0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440049 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffd03e23ca8 EFLAGS: 00000213 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440049 RDX: 0000000000000163 RSI: 0000000020000380 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004018d0 R13: 0000000000401960 R14: 0000000000000000 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..