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=-11.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C488EC433E0 for ; Sun, 27 Dec 2020 19:47:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84F2222522 for ; Sun, 27 Dec 2020 19:47:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726344AbgL0TqS (ORCPT ); Sun, 27 Dec 2020 14:46:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:57864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726123AbgL0TqS (ORCPT ); Sun, 27 Dec 2020 14:46:18 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id EF54422522; Sun, 27 Dec 2020 19:45:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1609098337; bh=rVnqSvmgdaQ4uBdVEXUoKyRB1XtdgtwKQn8q6bbqHAE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=qru1OfjxZnZJHo1yBGx0ggMCTDvESfnX2H0EVqY8wLvuL4uhe1RzyCetxjfNiX7dQ zDbQe6zi9OYRHs5B9+uDu7tS6vwwYE6w77h6y2PvTQqY2H0ZjTd6aWmrKhQ8BZg8hq 9H6L9bdLdSBb8aa985EeFhjXutWcb6bZgoTs8nzs= Date: Sun, 27 Dec 2020 11:45:34 -0800 From: Andrew Morton To: syzbot Cc: adobriyan@gmail.com, linux-kernel@vger.kernel.org, longman@redhat.com, sfr@canb.auug.org.au, syzkaller-bugs@googlegroups.com, vvs@virtuozzo.com, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov Subject: Re: BUG: unable to handle kernel NULL pointer dereference in call_rcu Message-Id: <20201227114534.1b3f407caaf9ec0e821f56f4@linux-foundation.org> In-Reply-To: <0000000000005ccf1b05b7665adc@google.com> References: <0000000000005ccf1b05b7665adc@google.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (cc KASAN developers) On Sat, 26 Dec 2020 15:25:14 -0800 syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 614cb589 Merge tag 'acpi-5.11-rc1-2' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=10a82a50d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=bf519e1e96191576 > dashboard link: https://syzkaller.appspot.com/bug?extid=9d3ede723bdc58553f13 > compiler: gcc (GCC) 10.1.0-syz 20200507 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11830e93500000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13d92057500000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+9d3ede723bdc58553f13@syzkaller.appspotmail.com > > BUG: kernel NULL pointer dereference, address: 0000000000000008 > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page > PGD 2d993067 P4D 2d993067 PUD 19a3c067 PMD 0 > Oops: 0000 [#1] PREEMPT SMP KASAN > CPU: 1 PID: 3852 Comm: kworker/1:2 Not tainted 5.10.0-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Workqueue: events free_ipc > RIP: 0010:kasan_record_aux_stack+0x77/0xb0 mm/kasan/generic.c:341 > Code: 48 f7 fe 8b 47 24 49 89 f0 48 29 d3 8d 70 ff 41 0f af f0 48 01 ce 48 39 f3 48 0f 46 f3 e8 81 e9 ff ff bf 00 08 00 00 48 89 c3 <8b> 40 08 89 43 0c e8 1e e6 ff ff 89 43 08 5b c3 48 8b 50 08 48 c7 > RSP: 0018:ffffc90002e6fae8 EFLAGS: 00010046 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888039800000 > RDX: 0000000000000078 RSI: ffff888039800000 RDI: 0000000000000800 > RBP: ffffffff837ef3a0 R08: 0000000000400000 R09: 000000000000002e > R10: ffffffff8132b7ea R11: 000000000000003f R12: 0000000000035b40 > R13: ffff888039800088 R14: ffffc90002e6fc08 R15: 0000000000000200 > FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000008 CR3: 0000000011841000 CR4: 00000000001506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > __call_rcu kernel/rcu/tree.c:2965 [inline] > call_rcu+0xbb/0x710 kernel/rcu/tree.c:3038 > ipc_rcu_putref+0x83/0xb0 ipc/util.c:505 > freeary+0x139c/0x1b30 ipc/sem.c:1188 > free_ipcs+0x98/0x1e0 ipc/namespace.c:112 > sem_exit_ns+0x1b/0x40 ipc/sem.c:260 > free_ipc_ns ipc/namespace.c:124 [inline] > free_ipc+0xf8/0x200 ipc/namespace.c:141 > process_one_work+0x98d/0x1630 kernel/workqueue.c:2275 > worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 > kthread+0x3b1/0x4a0 kernel/kthread.c:292 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 > Modules linked in: > CR2: 0000000000000008 > ---[ end trace 28dc093e61d44dc2 ]--- > RIP: 0010:kasan_record_aux_stack+0x77/0xb0 mm/kasan/generic.c:341 > Code: 48 f7 fe 8b 47 24 49 89 f0 48 29 d3 8d 70 ff 41 0f af f0 48 01 ce 48 39 f3 48 0f 46 f3 e8 81 e9 ff ff bf 00 08 00 00 48 89 c3 <8b> 40 08 89 43 0c e8 1e e6 ff ff 89 43 08 5b c3 48 8b 50 08 48 c7 > RSP: 0018:ffffc90002e6fae8 EFLAGS: 00010046 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888039800000 > RDX: 0000000000000078 RSI: ffff888039800000 RDI: 0000000000000800 > RBP: ffffffff837ef3a0 R08: 0000000000400000 R09: 000000000000002e > R10: ffffffff8132b7ea R11: 000000000000003f R12: 0000000000035b40 > R13: ffff888039800088 R14: ffffc90002e6fc08 R15: 0000000000000200 > FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000008 CR3: 0000000011841000 CR4: 00000000001506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > --- > 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. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches