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=-3.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 E1F70C433DB for ; Fri, 1 Jan 2021 00:50:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A57B6221E7 for ; Fri, 1 Jan 2021 00:50:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726980AbhAAAtx (ORCPT ); Thu, 31 Dec 2020 19:49:53 -0500 Received: from mail-il1-f197.google.com ([209.85.166.197]:42051 "EHLO mail-il1-f197.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726122AbhAAAtx (ORCPT ); Thu, 31 Dec 2020 19:49:53 -0500 Received: by mail-il1-f197.google.com with SMTP id p10so18853487ilo.9 for ; Thu, 31 Dec 2020 16:49:37 -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=f4jpcmyenKqYfST2LyQr30I+nGdhfXpwOSlfzY/gMRg=; b=J0veX9SpN6g37RbLzzkMxOKLAKKd3kC2zv52bkFwTDLt78RAv2pg/i1PL/Hb7zZOT/ MFfQeIToCaZUuoMlPw+ZIkhWUlZwM11t+xtdv/5hrOehpPC+H9+3KtoxDPO+S7m/q6nL GaHe0uClPqrQgPjyZ3G5UIio6pw8XLgdRXB0J0kZCfRalWzC/QNNLFMoePptzjxYPJ8z lHkv8+bhx0t0BLyBcw7FV7J7Xjlmi9d4MICyQTlfhZUcf4DL+yCUd9RlOZmd/mjyzxPd Q77k1eSUqfCK0OlLqsrLNL29p8hTEt/R/8mFrQNUNjPQ69PCBVLzeN0Nul635k1r4UTO 9bTQ== X-Gm-Message-State: AOAM532Mqkzq4IPWjNWhTC0HlPulv0oNHIiocVUhmPnZOOETceSFDRv+ nYebO3lGIF5SFotDkLyS/zX9DntHVd3CnGU3gNe+YytDTEiN X-Google-Smtp-Source: ABdhPJz5xy4u3Ybd++5GdqLQDigch4VAvgPEqKu2JTiKDWpaq0dnJo0DnSWd61C0FPgiaKY1aFv6nXGlpQzz7SzLD8LwnGBb8WKf MIME-Version: 1.0 X-Received: by 2002:a92:58dc:: with SMTP id z89mr58050886ilf.11.1609462151899; Thu, 31 Dec 2020 16:49:11 -0800 (PST) Date: Thu, 31 Dec 2020 16:49:11 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000d7f02105b7cc1b99@google.com> Subject: WARNING: suspicious RCU usage in xt_obj_to_user From: syzbot To: coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, kadlec@netfilter.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: f838f8d2 mfd: ab8500-debugfs: Remove extraneous seq_putc git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17074c47500000 kernel config: https://syzkaller.appspot.com/x/.config?x=7a43a64bad3fdb39 dashboard link: https://syzkaller.appspot.com/bug?extid=00399fa030c641ffc5ae compiler: gcc (GCC) 10.1.0-syz 20200507 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+00399fa030c641ffc5ae@syzkaller.appspotmail.com ============================= WARNING: suspicious RCU usage 5.10.0-syzkaller #0 Not tainted ----------------------------- kernel/sched/core.c:7877 Illegal context switch in RCU-bh read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 1 lock held by syz-executor.0/9704: #0: ffff888013794458 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 stack backtrace: CPU: 0 PID: 9704 Comm: syz-executor.0 Not tainted 5.10.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 ___might_sleep+0x229/0x2c0 kernel/sched/core.c:7877 __might_fault+0x6e/0x180 mm/memory.c:5014 xt_obj_to_user+0x31/0x110 net/netfilter/x_tables.c:277 xt_target_to_user+0xa8/0x200 net/netfilter/x_tables.c:323 copy_entries_to_user net/ipv4/netfilter/arp_tables.c:705 [inline] get_entries net/ipv4/netfilter/arp_tables.c:866 [inline] do_arpt_get_ctl+0x733/0x8f0 net/ipv4/netfilter/arp_tables.c:1450 nf_getsockopt+0x72/0xd0 net/netfilter/nf_sockopt.c:116 ip_getsockopt net/ipv4/ip_sockglue.c:1777 [inline] ip_getsockopt+0x164/0x1c0 net/ipv4/ip_sockglue.c:1756 tcp_getsockopt+0x86/0xd0 net/ipv4/tcp.c:4141 __sys_getsockopt+0x219/0x4c0 net/socket.c:2156 __do_sys_getsockopt net/socket.c:2171 [inline] __se_sys_getsockopt net/socket.c:2168 [inline] __x64_sys_getsockopt+0xba/0x150 net/socket.c:2168 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ef5a Code: b8 34 01 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 cd 9f fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 aa 9f fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007ffcf91ed728 EFLAGS: 00000212 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffcf91ed790 RCX: 000000000045ef5a RDX: 0000000000000061 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffcf91ed73c R09: 000000000000000a R10: 00007ffcf91ed790 R11: 0000000000000212 R12: 00007ffcf91ed73c R13: 0000000000000000 R14: 0000000000000032 R15: 000000000003354d --- 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.