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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 00B38C43603 for ; Thu, 5 Dec 2019 04:35:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC73F206DB for ; Thu, 5 Dec 2019 04:35:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=axtens.net header.i=@axtens.net header.b="HTnzmMsS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728892AbfLEEf0 (ORCPT ); Wed, 4 Dec 2019 23:35:26 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:34969 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728873AbfLEEf0 (ORCPT ); Wed, 4 Dec 2019 23:35:26 -0500 Received: by mail-pj1-f67.google.com with SMTP id w23so756807pjd.2 for ; Wed, 04 Dec 2019 20:35:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axtens.net; s=google; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=s6emKmGGeuSq3wtIVxjBKVR6ZpCN8AX3rs92e/sQ08s=; b=HTnzmMsSBoONgPFSO6kOgPwH5zOZehEChmShYIuAo0k4JTBQNF3A5wgx2GKkGvWf0/ S8wIIqluaiR7t7sEd8vDlFYt+v+8pBRbWU2LvgNKERIMYCO/15zH23xUkm5+HaCbsXdi KrdfsJfxfqTl+g3UG1SnUBAB4DY29MLiQVxfc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=s6emKmGGeuSq3wtIVxjBKVR6ZpCN8AX3rs92e/sQ08s=; b=HhI0O2PwYoSGndAXjGuRQxMNzZ4Nnm1WBHIhpO1fuyzoTA+SZcJVyM9f3pm4FGUtzm NKKNtNpHFQKuSmX+FRXIVoflbIfrGmn+dYTLwK835zRq4R4CJUbnAMCrybs01IajYuoo sq2tWPxdgOiMG5sXY41XyXNjWgtCnnkdVccZfZLgMPgI7I3dsT0mLZIVLZ7apoeRAoFH ztaztqFwrQgNEgG3PACZHND//+DasI2vINTXwcetBHHp2gNIwIt+fpaF2fDfeuHKJ2e0 8NUi5bGV71qrzum0949JrIa1p458kuuxTE36Zb37R5xmm4kfkWzZmntV/v8steT944i4 r1Jw== X-Gm-Message-State: APjAAAUdOuWLiGVS+2I90MLnhqYRez6HrZMzUbNQ0leOFpDQGTJs8x3E 1XeMkXQgIIa4v06TLfQ2QzOOfg== X-Google-Smtp-Source: APXvYqxCZmeC4c8H+1S3gozzuwiEdfr5IAET6UGkXj4FIbbXUkTX+Q/yZHHnB0KOldDQ9QcNbSYcCw== X-Received: by 2002:a17:90a:bb0b:: with SMTP id u11mr7305972pjr.12.1575520525179; Wed, 04 Dec 2019 20:35:25 -0800 (PST) Received: from localhost (2001-44b8-1113-6700-7daa-d2ea-7edb-cfe8.static.ipv6.internode.on.net. [2001:44b8:1113:6700:7daa:d2ea:7edb:cfe8]) by smtp.gmail.com with ESMTPSA id c184sm10147599pfa.39.2019.12.04.20.35.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Dec 2019 20:35:24 -0800 (PST) From: Daniel Axtens To: Dmitry Vyukov , syzbot , kasan-dev Cc: Andrii Nakryiko , Alexei Starovoitov , bpf , Daniel Borkmann , Martin KaFai Lau , LKML , netdev , Song Liu , syzkaller-bugs , Yonghong Song , Andrey Ryabinin Subject: Re: BUG: unable to handle kernel paging request in pcpu_alloc In-Reply-To: References: <000000000000314c120598dc69bd@google.com> Date: Thu, 05 Dec 2019 15:35:21 +1100 Message-ID: <877e3be6eu.fsf@dja-thinkpad.axtens.net> MIME-Version: 1.0 Content-Type: text/plain Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org >> HEAD commit: 1ab75b2e Add linux-next specific files for 20191203 >> git tree: linux-next >> console output: https://syzkaller.appspot.com/x/log.txt?x=10edf2eae00000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=de1505c727f0ec20 >> dashboard link: https://syzkaller.appspot.com/bug?extid=82e323920b78d54aaed5 >> compiler: gcc (GCC) 9.0.0 20181231 (experimental) >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=156ef061e00000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11641edae00000 >> >> IMPORTANT: if you fix the bug, please add the following tag to the commit: >> Reported-by: syzbot+82e323920b78d54aaed5@syzkaller.appspotmail.com > > +Daniel, is it the same as: > https://syzkaller.appspot.com/bug?id=f6450554481c55c131cc23d581fbd8ea42e63e18 > If so, is it possible to make KASAN detect this consistently with the > same crash type so that syzbot does not report duplicates? It looks like both of these occur immediately after failure injection. I think my assumption that I could ignore the chance of failures in the per-cpu allocation path will have to be revisited. That's annoying. I'll try to spin something today but Andrey feel free to pip me at the post again :) I'm not 100% confident to call them dups just yet, but I'm about 80% confident that they are. Regards, Daniel > >> RDX: 000000000000003c RSI: 0000000020000080 RDI: 0c00000000000000 >> RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000018 >> R13: 0000000000000004 R14: 0000000000000005 R15: 0000000000000000 >> BUG: unable to handle page fault for address: fffff91ffff00000 >> #PF: supervisor read access in kernel mode >> #PF: error_code(0x0000) - not-present page >> PGD 21ffe6067 P4D 21ffe6067 PUD aa56c067 PMD aa56d067 PTE 0 >> Oops: 0000 [#1] PREEMPT SMP KASAN >> CPU: 1 PID: 8999 Comm: syz-executor865 Not tainted >> 5.4.0-next-20191203-syzkaller #0 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> Google 01/01/2011 >> RIP: 0010:memory_is_nonzero mm/kasan/generic.c:121 [inline] >> RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:135 [inline] >> RIP: 0010:memory_is_poisoned mm/kasan/generic.c:166 [inline] >> RIP: 0010:check_memory_region_inline mm/kasan/generic.c:182 [inline] >> RIP: 0010:check_memory_region+0x9c/0x1a0 mm/kasan/generic.c:192 >> Code: c9 4d 0f 49 c1 49 c1 f8 03 45 85 c0 0f 84 10 01 00 00 41 83 e8 01 4e >> 8d 44 c0 08 eb 0d 48 83 c0 08 4c 39 c0 0f 84 a7 00 00 00 <48> 83 38 00 74 >> ed 4c 8d 40 08 eb 09 48 83 c0 01 49 39 c0 74 53 80 >> RSP: 0018:ffffc90001f67a80 EFLAGS: 00010216 >> RAX: fffff91ffff00000 RBX: fffff91ffff01000 RCX: ffffffff819e1589 >> RDX: 0000000000000001 RSI: 0000000000008000 RDI: ffffe8ffff800000 >> RBP: ffffc90001f67a98 R08: fffff91ffff01000 R09: 0000000000001000 >> R10: fffff91ffff00fff R11: ffffe8ffff807fff R12: fffff91ffff00000 >> R13: 0000000000008000 R14: 0000000000000000 R15: ffff88821fffd100 >> FS: 00000000011a7880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: fffff91ffff00000 CR3: 00000000a94ad000 CR4: 00000000001406e0 >> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >> Call Trace: >> memset+0x24/0x40 mm/kasan/common.c:107 >> memset include/linux/string.h:410 [inline] >> pcpu_alloc+0x589/0x1380 mm/percpu.c:1734 >> __alloc_percpu_gfp+0x28/0x30 mm/percpu.c:1783 >> bpf_array_alloc_percpu kernel/bpf/arraymap.c:35 [inline] >> array_map_alloc+0x698/0x7d0 kernel/bpf/arraymap.c:159 >> find_and_alloc_map kernel/bpf/syscall.c:123 [inline] >> map_create kernel/bpf/syscall.c:654 [inline] >> __do_sys_bpf+0x478/0x3810 kernel/bpf/syscall.c:3012 >> __se_sys_bpf kernel/bpf/syscall.c:2989 [inline] >> __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:2989 >> do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 >> entry_SYSCALL_64_after_hwframe+0x49/0xbe >> RIP: 0033:0x442f99 >> Code: e8 ec 09 03 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 cb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 >> RSP: 002b:00007ffc8aa156d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 >> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000442f99 >> RDX: 000000000000003c RSI: 0000000020000080 RDI: 0c00000000000000 >> RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000018 >> R13: 0000000000000004 R14: 0000000000000005 R15: 0000000000000000 >> Modules linked in: >> CR2: fffff91ffff00000 >> ---[ end trace 449f8b43dad6ffb8 ]--- >> RIP: 0010:memory_is_nonzero mm/kasan/generic.c:121 [inline] >> RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:135 [inline] >> RIP: 0010:memory_is_poisoned mm/kasan/generic.c:166 [inline] >> RIP: 0010:check_memory_region_inline mm/kasan/generic.c:182 [inline] >> RIP: 0010:check_memory_region+0x9c/0x1a0 mm/kasan/generic.c:192 >> Code: c9 4d 0f 49 c1 49 c1 f8 03 45 85 c0 0f 84 10 01 00 00 41 83 e8 01 4e >> 8d 44 c0 08 eb 0d 48 83 c0 08 4c 39 c0 0f 84 a7 00 00 00 <48> 83 38 00 74 >> ed 4c 8d 40 08 eb 09 48 83 c0 01 49 39 c0 74 53 80 >> RSP: 0018:ffffc90001f67a80 EFLAGS: 00010216 >> RAX: fffff91ffff00000 RBX: fffff91ffff01000 RCX: ffffffff819e1589 >> RDX: 0000000000000001 RSI: 0000000000008000 RDI: ffffe8ffff800000 >> RBP: ffffc90001f67a98 R08: fffff91ffff01000 R09: 0000000000001000 >> R10: fffff91ffff00fff R11: ffffe8ffff807fff R12: fffff91ffff00000 >> R13: 0000000000008000 R14: 0000000000000000 R15: ffff88821fffd100 >> FS: 00000000011a7880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: fffff91ffff00000 CR3: 00000000a94ad000 CR4: 00000000001406e0 >> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >> >> >> --- >> 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. >> syzbot can test patches for this bug, for details see: >> https://goo.gl/tpsmEJ#testing-patches >> >> -- >> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. >> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com. >> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/000000000000314c120598dc69bd%40google.com.