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_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 3C51EC282CE for ; Tue, 4 Jun 2019 13:56:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DD4024BC2 for ; Tue, 4 Jun 2019 13:56:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727533AbfFDN4H (ORCPT ); Tue, 4 Jun 2019 09:56:07 -0400 Received: from mail-it1-f199.google.com ([209.85.166.199]:42876 "EHLO mail-it1-f199.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727504AbfFDN4H (ORCPT ); Tue, 4 Jun 2019 09:56:07 -0400 Received: by mail-it1-f199.google.com with SMTP id s18so69873itl.7 for ; Tue, 04 Jun 2019 06:56:06 -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:message-id:subject:from:to; bh=e0x3CjfxT+Tc9OfQE9UyUP0v/CUgs1KGy0Ok9Cy7y8Q=; b=Ncolpllqp7xPDCQ7voftSW2tGlCzGnnMNCp7h7PHu/HMhQ8iTTkKqL/aJmSZm5c/nn 8TVcqACMOvYYQSiqgOifzGU37mWK8vNMJnquX2E8A8PuipbPYd/jb2222Alcv4j5a/aV 2ESPWp3CrdYhN2k7/bma8h8B47MBKDgZj8nq+95lf4LIqbxB+jvGZK+A/49qHvHAjxb+ URqBH4MPCgkMePQY7DnuSchvIreEJz+cgBtVb4iGZgyeKNrE24xQDKsNfSjKlLzA15tc l7uYwkq4iQUS+oTdOG3gXJ8hxFhLSmg5GB0f3u3BxUkBnImicHEPM5MseXML+pDbFspF FWmg== X-Gm-Message-State: APjAAAXkgpnyTtdmrTDSvccE6r1xBuDLWkcbBNjXpP6gaQmYAcrrw7yn Jltbm/OVabKW2MaGaJsInV6Gp9uPXHkGhCtF3ed9v0EQpNFb X-Google-Smtp-Source: APXvYqxswE3V/GpTEDke+LgJdIgEgE7AHZepq4QIp7VgGjhnjLYEetNn3M4bxurDFjITYWRV/6FI9+281KrpB9Zvomf/8KvUcPy8 MIME-Version: 1.0 X-Received: by 2002:a5d:9f12:: with SMTP id q18mr16396879iot.250.1559656566027; Tue, 04 Jun 2019 06:56:06 -0700 (PDT) Date: Tue, 04 Jun 2019 06:56:06 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000097025d058a7fd785@google.com> Subject: KASAN: slab-out-of-bounds Read in css_task_iter_advance From: syzbot To: ast@kernel.org, bpf@vger.kernel.org, cgroups@vger.kernel.org, daniel@iogearbox.net, hannes@cmpxchg.org, kafai@fb.com, linux-kernel@vger.kernel.org, lizefan@huawei.com, netdev@vger.kernel.org, songliubraving@fb.com, syzkaller-bugs@googlegroups.com, tj@kernel.org, yhs@fb.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 56b697c6 Add linux-next specific files for 20190604 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=170d747ca00000 kernel config: https://syzkaller.appspot.com/x/.config?x=4248d6bc70076f7d dashboard link: https://syzkaller.appspot.com/bug?extid=9343b7623bc03dc680c1 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+9343b7623bc03dc680c1@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-out-of-bounds in css_task_iter_advance+0x49b/0x540 kernel/cgroup/cgroup.c:4507 Read of size 4 at addr ffff88809ae59d64 by task syz-executor.2/28895 CPU: 1 PID: 28895 Comm: syz-executor.2 Not tainted 5.2.0-rc3-next-20190604 #8 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 css_task_iter_advance+0x49b/0x540 kernel/cgroup/cgroup.c:4507 css_task_iter_start+0x18b/0x230 kernel/cgroup/cgroup.c:4543 update_tasks_flags+0x85/0x100 kernel/cgroup/cpuset.c:1836 update_flag+0x232/0x470 kernel/cgroup/cpuset.c:1886 cpuset_write_u64+0x222/0x270 kernel/cgroup/cpuset.c:2268 cgroup_file_write+0x4db/0x790 kernel/cgroup/cgroup.c:3727 kernfs_fop_write+0x2b8/0x480 fs/kernfs/file.c:316 __vfs_write+0x8a/0x110 fs/read_write.c:494 vfs_write+0x268/0x5d0 fs/read_write.c:558 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8d15ef2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 0000000000000011 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8d15ef36d4 R13: 00000000004c8eb1 R14: 00000000004dfb68 R15: 00000000ffffffff Allocated by task 9803: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:444 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3482 getname_flags fs/namei.c:138 [inline] getname_flags+0xd6/0x5b0 fs/namei.c:128 getname fs/namei.c:209 [inline] do_renameat2+0x199/0xc40 fs/namei.c:4543 __do_sys_rename fs/namei.c:4671 [inline] __se_sys_rename fs/namei.c:4669 [inline] __x64_sys_rename+0x61/0x80 fs/namei.c:4669 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9803: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3692 putname+0xef/0x130 fs/namei.c:259 do_renameat2+0x2b4/0xc40 fs/namei.c:4647 __do_sys_rename fs/namei.c:4671 [inline] __se_sys_rename fs/namei.c:4669 [inline] __x64_sys_rename+0x61/0x80 fs/namei.c:4669 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88809ae58440 which belongs to the cache names_cache of size 4096 The buggy address is located 2340 bytes to the right of 4096-byte region [ffff88809ae58440, ffff88809ae59440) The buggy address belongs to the page: page:ffffea00026b9600 refcount:1 mapcount:0 mapping:ffff8880aa593ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea00018b4308 ffffea0001afb488 ffff8880aa593ac0 raw: 0000000000000000 ffff88809ae58440 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809ae59c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809ae59c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88809ae59d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809ae59d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809ae59e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- 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#status for how to communicate with syzbot.