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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 0802FC2BBE2 for ; Wed, 4 Dec 2019 08:18:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BED1020675 for ; Wed, 4 Dec 2019 08:18:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bNmjEXsL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727249AbfLDISa (ORCPT ); Wed, 4 Dec 2019 03:18:30 -0500 Received: from mail-qv1-f68.google.com ([209.85.219.68]:46054 "EHLO mail-qv1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725951AbfLDIS3 (ORCPT ); Wed, 4 Dec 2019 03:18:29 -0500 Received: by mail-qv1-f68.google.com with SMTP id c2so2697121qvp.12 for ; Wed, 04 Dec 2019 00:18:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=IOrpunYOl9f5imurR4iaLW0MWbzeDjpl3e51EdkQBxM=; b=bNmjEXsL3LXOWJr9pXvuWuP7goPByOjxlTTmOiZ5PMGOjue/eC4wln79RfQ366yy9S HeBWDH5pUfiVlVCsLJwIAGMoIpjZSj6nsK3C4K8z5CVrS2FzUIyL/RcWGJ9WGaNBIqZj YfXk9dXBSuLc/GwkOcvpk6Hxs8qsQVgPPugFmRoISvxRC+6DXXVmNul4KNaiK5niFWt1 4+8dr4c5G9RFqkASuKUC7Rl5IDx+rGWPyPU8AH4jvIxsOF0aprCm37ldX7d5BZgD+3qA ZvZLdb5RMvmdFQ1mWDAeQ5eftYCCorw26I7O+8uIFn5YwjB2lzwlAY9TB5h04pf1xO9r jGYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=IOrpunYOl9f5imurR4iaLW0MWbzeDjpl3e51EdkQBxM=; b=mBX34fp+fYJeWuJ7rv448itsBfTdBIpSvEtqaslqci6iWh6ecSBOrhPVarI6SLXWV4 EQJxeT4IGS+PEAnQaIi/t0FH7IS9YCrehjid2tbMCNE2mQ2RX9pow8U41+UFEYhe2+KG AWKt8mKKUrmqdYjuXLdREQ8p+MVTh7FOZiyk+9WoIi1rE9RD3tcQxw03eoibBqKKf3+p /nPVXM2+MJMKRM68hljUbBAbObMSN3sOoFzoL0z7g+WTe0dVX/dGuvj7gDNr3y6AZqx2 L3ShUAdZ2rVqVA513DWNl2WY2qdOFUDje36UcPEZpfIpNjletKIGQMe22e10xn6oP+ou ngZw== X-Gm-Message-State: APjAAAXYFRMYk+fZCUQPxGekx3m2HTsc7ASRmx07nWuQXx+EFtchSTwP vFuv9ejZWrCPKrzj1pDm5GxQIdbRiRR9wPiudtncPw== X-Google-Smtp-Source: APXvYqysBvTqFphuPETAtOdHY0mhVi0A/Kh6B/KHBpk95x6M/MEXLFv73wtPkH1xBpxO5iQ1WYoLAKw3migOv4YHrBU= X-Received: by 2002:a0c:c125:: with SMTP id f34mr1555482qvh.22.1575447507606; Wed, 04 Dec 2019 00:18:27 -0800 (PST) MIME-Version: 1.0 References: <000000000000314c120598dc69bd@google.com> In-Reply-To: <000000000000314c120598dc69bd@google.com> From: Dmitry Vyukov Date: Wed, 4 Dec 2019 09:18:16 +0100 Message-ID: Subject: Re: BUG: unable to handle kernel paging request in pcpu_alloc To: syzbot , kasan-dev , Daniel Axtens Cc: Andrii Nakryiko , Alexei Starovoitov , bpf , Daniel Borkmann , Martin KaFai Lau , LKML , netdev , Song Liu , syzkaller-bugs , Yonghong Song Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 4, 2019 at 9:15 AM syzbot wrote: > > Hello, > > syzbot found the following crash on: > > 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? > 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.