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 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 6E87AC43612 for ; Tue, 18 Dec 2018 12:41:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 484FC2186A for ; Tue, 18 Dec 2018 12:41:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726631AbeLRMlE (ORCPT ); Tue, 18 Dec 2018 07:41:04 -0500 Received: from mail-it1-f200.google.com ([209.85.166.200]:38272 "EHLO mail-it1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726605AbeLRMlE (ORCPT ); Tue, 18 Dec 2018 07:41:04 -0500 Received: by mail-it1-f200.google.com with SMTP id m128so3139561itd.3 for ; Tue, 18 Dec 2018 04:41:03 -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=mUfbHQ74N9uH9Gs2f8y9eJBQ3F7xR2hO6D0FQiQnrTE=; b=jhELDCV5wksetn8gEMyUiAGBoW/39D3gvuwaKA60C8RfRTwwkR1SONzK5gtg1QeKXp cUjmJzLI0cWCs3xMVxvrCZMi6Ovfj3evVOtAdKgJfN0bmtJqI3U+6cawmMnrjAsVG+N1 wLFNw3g2ibcKl0j4ZbrjAbCcBtHRfAmrjQeTWUxHmWftqekWXuKnXU1osHs/XH922G0X XGkBNVwIzY81cwQiADKWbHoGnL+yW0PH41UTERi5nwERcr6jIMTTub/EcJ6gsTcIdFJF crfbbIyQc1+BX2Tbrm3BM6Pim6l3Ttn9tM3fwJqF5cAJlALL2gUvvJ4niJwnZAhijRAr 9yoA== X-Gm-Message-State: AA+aEWZciWWQpBvFdVtt2k+tnX+Ky6D+syatVn7S/AsceKu/HtVyuvX6 QoGWbdCMF632axEXPbAosnQUCG+vFBlbPjjrk5tYLRfsqHF2 X-Google-Smtp-Source: AFSGD/X8jxKZtOXoTaBL+j49PJOgrlBDsy5WVPt5wxeATTydgm+p6MLOJpq1xO/04tXZum5cGibvsRKJ7x5sKUrB1im1Ad/eUPJj MIME-Version: 1.0 X-Received: by 2002:a02:2b18:: with SMTP id h24mr14084363jaa.7.1545136862827; Tue, 18 Dec 2018 04:41:02 -0800 (PST) Date: Tue, 18 Dec 2018 04:41:02 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000d69d87057d4b3550@google.com> Subject: KMSAN: kernel-infoleak in video_usercopy From: syzbot To: glider@google.com, hansverk@cisco.com, hdegoede@redhat.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, mchehab@kernel.org, niklas.soderlund+renesas@ragnatech.se, paul.kocialkowski@bootlin.com, sakari.ailus@linux.intel.com, samitolvanen@google.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: 0a602458c72c kmsan: random: another take at unpoisoning CR.. git tree: kmsan console output: https://syzkaller.appspot.com/x/log.txt?x=12f2cd5d400000 kernel config: https://syzkaller.appspot.com/x/.config?x=9b071100dcf8e641 dashboard link: https://syzkaller.appspot.com/bug?extid=4f021cf3697781dbd9fb compiler: clang version 8.0.0 (trunk 348261) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15d6b21b400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f15885400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+4f021cf3697781dbd9fb@syzkaller.appspotmail.com ================================================================== BUG: KMSAN: kernel-infoleak in _copy_to_user+0x1a4/0x250 lib/usercopy.c:32 CPU: 0 PID: 6254 Comm: syz-executor456 Not tainted 4.20.0-rc5+ #2 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+0x1c9/0x220 lib/dump_stack.c:113 kmsan_report+0x12d/0x290 mm/kmsan/kmsan.c:682 kmsan_internal_check_memory+0x334/0xa60 mm/kmsan/kmsan.c:742 kmsan_copy_to_user+0x8d/0xa0 mm/kmsan/kmsan_hooks.c:604 _copy_to_user+0x1a4/0x250 lib/usercopy.c:32 copy_to_user include/linux/uaccess.h:177 [inline] video_usercopy+0x16c9/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3066 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:713 [inline] __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x445659 Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff7a472ada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000445659 RDX: 0000000020000000 RSI: 0000000080885659 RDI: 0000000000000003 RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c R13: 6469762f7665642f R14: 00007ff7a472b9c0 R15: 00000000006dad2c Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:247 [inline] kmsan_save_stack mm/kmsan/kmsan.c:262 [inline] kmsan_internal_chain_origin+0x162/0x260 mm/kmsan/kmsan.c:470 kmsan_memcpy_memmove_metadata+0x1a9/0xf30 mm/kmsan/kmsan.c:345 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:363 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:148 __v4l2_event_dequeue+0x2f8/0x730 drivers/media/v4l2-core/v4l2-event.c:54 v4l2_event_dequeue+0x41c/0x560 drivers/media/v4l2-core/v4l2-event.c:81 v4l_dqevent+0xba/0xe0 drivers/media/v4l2-core/v4l2-ioctl.c:2427 __video_do_ioctl+0x1975/0x1fc0 drivers/media/v4l2-core/v4l2-ioctl.c:2853 video_usercopy+0x8ae/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3035 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:713 [inline] __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:247 [inline] kmsan_save_stack mm/kmsan/kmsan.c:262 [inline] kmsan_internal_chain_origin+0x162/0x260 mm/kmsan/kmsan.c:470 kmsan_memcpy_memmove_metadata+0x1a9/0xf30 mm/kmsan/kmsan.c:345 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:363 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:148 __v4l2_event_queue_fh+0xd2d/0x1260 drivers/media/v4l2-core/v4l2-event.c:145 v4l2_event_queue_fh+0x1a1/0x270 drivers/media/v4l2-core/v4l2-event.c:185 v4l2_ctrl_add_event+0x952/0xc20 drivers/media/v4l2-core/v4l2-ctrls.c:4099 v4l2_event_subscribe+0xf75/0x1240 drivers/media/v4l2-core/v4l2-event.c:251 v4l2_ctrl_subscribe_event+0xb6/0x110 drivers/media/v4l2-core/v4l2-ctrls.c:4156 v4l_subscribe_event+0x9e/0xc0 drivers/media/v4l2-core/v4l2-ioctl.c:2433 __video_do_ioctl+0x1975/0x1fc0 drivers/media/v4l2-core/v4l2-ioctl.c:2853 video_usercopy+0x8ae/0x17d0 drivers/media/v4l2-core/v4l2-ioctl.c:3035 video_ioctl2+0x9f/0xb0 drivers/media/v4l2-core/v4l2-ioctl.c:3079 v4l2_ioctl+0x23f/0x270 drivers/media/v4l2-core/v4l2-dev.c:364 do_vfs_ioctl+0xf36/0x2d30 fs/ioctl.c:46 ksys_ioctl fs/ioctl.c:713 [inline] __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Local variable description: ----ev@v4l2_ctrl_add_event Variable was created at: v4l2_ctrl_add_event+0x6e/0xc20 drivers/media/v4l2-core/v4l2-ctrls.c:4080 v4l2_event_subscribe+0xf75/0x1240 drivers/media/v4l2-core/v4l2-event.c:251 Bytes 44-71 of 136 are uninitialized Memory access of size 136 starts at ffff8881bcc903c0 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