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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA243C433EF for ; Thu, 10 Feb 2022 10:50:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240215AbiBJKuS (ORCPT ); Thu, 10 Feb 2022 05:50:18 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:59098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240208AbiBJKuQ (ORCPT ); Thu, 10 Feb 2022 05:50:16 -0500 Received: from mail-il1-f198.google.com (mail-il1-f198.google.com [209.85.166.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 086A4100A for ; Thu, 10 Feb 2022 02:50:18 -0800 (PST) Received: by mail-il1-f198.google.com with SMTP id q15-20020a92ca4f000000b002be3e7707ffso3710490ilo.4 for ; Thu, 10 Feb 2022 02:50:17 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=sxYpZJUZ2c9zNF0g11fgItZpAgYz7w3rafFkaJxtZEQ=; b=6Eutxt3C58LvlZ/DWvWYx53UDpaTPwMUCdf+/rkGpnLuS4MS9JQH3AihrT1yAi2cCw EIFRAYf7bm9P+qYdZfAVCwvFUxf3l1bsk//13A0fdiXYmdYTVwGDEE/PVFmK9vUJ4w/G 5I3do46AIjmJ8eBlvko+mru1QPbbLkN4CMLp/s/JCxTpV4r2+hJudIyInXF82K9f0XBw GoyKMNn91Yvk7LKsVfMSBYm5xINaMXKudLsVvwWxhbFFZDQYZnWK8ITGycZX6uOGxSh/ JAARFAAkFi6KOyIC/5sOifVyoXaAQHJYlkK0/jzkfQqGP9pQWpuj7rWblTZJkFPjlBcG t/Wg== X-Gm-Message-State: AOAM5338dGFjOgemBtR+YdueiibqpuDZ/SF6fkGBOVwj+/biolTiJVcu LuUN3knp+YjgZkr6PDj/A0IIikIXVkxYEDKswd8UnkEyDg64 X-Google-Smtp-Source: ABdhPJzDPwxNgGEw7MSf2dUinV4AhG1lZH2BM4eClEPzLE93HkKhYeXKN5whaoqHy9jESUgvFBAgh+EYiT8naivCOjHaQBhUIyma MIME-Version: 1.0 X-Received: by 2002:a6b:7219:: with SMTP id n25mr3519606ioc.12.1644490217356; Thu, 10 Feb 2022 02:50:17 -0800 (PST) Date: Thu, 10 Feb 2022 02:50:17 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000003e009a05d7a7b77f@google.com> Subject: [syzbot] KCSAN: data-race in copy_page_to_iter / strncpy (4) From: syzbot To: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tytso@mit.edu Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: e6251ab4551f Merge tag 'nfs-for-5.17-2' of git://git.linux.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=109133b4700000 kernel config: https://syzkaller.appspot.com/x/.config?x=1dcc3374da7c1f7c dashboard link: https://syzkaller.appspot.com/bug?extid=88a9b535e28311efdcd4 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+88a9b535e28311efdcd4@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in copy_page_to_iter / strncpy write to 0xffff888108b1b488 of 1 bytes by task 16090 on cpu 1: strncpy+0xcf/0x150 lib/string.c:114 ext4_sample_last_mounted fs/ext4/file.c:828 [inline] ext4_file_open+0x3a6/0x4e0 fs/ext4/file.c:847 do_dentry_open+0x52c/0x860 fs/open.c:824 vfs_open+0x43/0x50 fs/open.c:959 do_open fs/namei.c:3476 [inline] path_openat+0x170c/0x1f30 fs/namei.c:3609 do_filp_open+0x105/0x220 fs/namei.c:3636 do_sys_openat2+0xb5/0x2b0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_open fs/open.c:1238 [inline] __se_sys_open fs/open.c:1234 [inline] __x64_sys_open+0xe2/0x110 fs/open.c:1234 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888108b1b400 of 1024 bytes by task 10450 on cpu 0: instrument_copy_to_user include/linux/instrumented.h:119 [inline] copyout lib/iov_iter.c:154 [inline] copy_page_to_iter_iovec lib/iov_iter.c:226 [inline] __copy_page_to_iter lib/iov_iter.c:850 [inline] copy_page_to_iter+0x2cb/0x950 lib/iov_iter.c:878 copy_folio_to_iter include/linux/uio.h:153 [inline] filemap_read+0x1126/0x1430 mm/filemap.c:2727 blkdev_read_iter+0x2cc/0x380 block/fops.c:614 call_read_iter include/linux/fs.h:2068 [inline] new_sync_read fs/read_write.c:400 [inline] vfs_read+0x66c/0x750 fs/read_write.c:481 ksys_read+0xd9/0x190 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [inline] __se_sys_read fs/read_write.c:627 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:627 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10450 Comm: udevd Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== I/O error, dev loop2, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0 --- This report 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 issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.