From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f70.google.com (mail-io1-f70.google.com [209.85.166.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0021A1EC01C for ; Wed, 4 Sep 2024 07:04:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725433445; cv=none; b=bpXfqL9QZpsDYIfxE3ma29Qneiuz0EsVoZH7FlFsjipf97utKojMy2g2ud/CX2Xrl+kxs+rz2gOB8+yFvABNExXHGh/41bXm0pucJ1ovjTl7zALXkKiqXeSnAed9X2lT8JbkzYvqhwwoFj4V84KrVdkn4a1ShV2ubaeCgSAuyQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725433445; c=relaxed/simple; bh=i3+Hf1ab/g+31CTHiFkSxmRlt36SammWuwiumwNX3OQ=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=nAZoicLrnURH3hW7HEZWiXxDEhHY8ShvGXvHASUjp/52VIc1F57WEyKID3uaZbkxh4xmhYrRQVSD2VlglU5azyXk7znfMUhocXD4U/AWmSCZ1+q/e+yQtU3asQpvKgzCh1okyousSrtV6CHn1se4th7MkJncrWvU1R/dsAZQ6ZY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f70.google.com with SMTP id ca18e2360f4ac-82a321567d4so520332939f.0 for ; Wed, 04 Sep 2024 00:04:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725433443; x=1726038243; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ecSvyV5tZ6GP6zSVIFI8UpENf3GOc6t1nuzW2gOeIkQ=; b=YFj4TG2nshZjvvRP1drb4RnSzwv/Pql8suLkwZmAFmtS5jKXSu2It+6VZ+64kf8JCK Qn2Y3dYe9cyZTN641DfREI1LfBpvrM+523clNqfxzsopV2/DlAeQe8ldie4q2MsIvuh8 I0LFrv1PfMHwtHUKYzOSoJjrBfRY0dmNBTWOrBOjknigPt18Qzk6ca+Mjs233O89eMnw lpS4mckcZ14Y368itlqFSGppuWPDaiHFSHj2ogg6960ji8udJtA5zM7aEdwSyBYM2M/u u0ZpL/hKiAM0q5iNqdxwO3HDXArSEC/QmMpHRGjuw7puZTmdQz/5Q4IB9saKhL4s7KGd An1g== X-Forwarded-Encrypted: i=1; AJvYcCWR6Guim16z8u9IOcqWh1KryTnBfPvEFcyb13EY51Uc71EbX8uU2rHvhAIsPme1YXIq51FRHcCsmVHbLHI=@vger.kernel.org X-Gm-Message-State: AOJu0YzEyJNP/jJ//ABhOoWXH/6dg8U7199ppLBoV+HkJDJ/5UN//xvZ nSzbWupUvNSzVyxcqityQjer2FB04pgtFhmf73BJDFaIB9qzTXIIHfmsnkukEMpQtPNB9muSOoq UfcLWbBdfG0z3Fn2tzdU+gZ/j2IkivXlMDSS2VYPJoA9fz0zxZf6JXHg= X-Google-Smtp-Source: AGHT+IH1Z06igPV7QXz7rOHaiCvWHz7pxAms/IIiNM9fGg0u3r0rzP9MAvDeryFoRqbGny3c/AAGTAyolrfQf5fl0W3B9z5/QI9K Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6602:3409:b0:82a:3236:9d22 with SMTP id ca18e2360f4ac-82a32369dbfmr44792439f.4.1725433443077; Wed, 04 Sep 2024 00:04:03 -0700 (PDT) Date: Wed, 04 Sep 2024 00:04:03 -0700 In-Reply-To: <66d79038.170a0220.22e970.97fd@mx.google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000756497062145c7a0@google.com> Subject: Re: [syzbot] [overlayfs?] BUG: unable to handle kernel NULL pointer dereference in __lookup_slow (3) From: syzbot To: andrew.kanner@gmail.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: BUG: unable to handle kernel NULL pointer dereference in __lookup_slow loop0: detected capacity change from 0 to 64 overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 800000001f849067 P4D 800000001f849067 PUD 1fabf067 PMD 0 Oops: Oops: 0010 [#1] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 6157 Comm: syz.0.15 Not tainted 6.11.0-rc5-syzkaller-00017-g7d6899fb69d2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc9000492f558 EFLAGS: 00010246 RAX: 1ffffffff17f1868 RBX: ffffffff8bf8c340 RCX: ffff888024845a00 RDX: 0000000000000000 RSI: ffff8880699ead38 RDI: ffff888069bac018 RBP: ffffc9000492f670 R08: ffffffff820c2f53 R09: 1ffffffff29ad1f5 R10: dffffc0000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff8880699ead38 R14: 1ffff1100d33d5a7 R15: 1ffff92000925eb0 FS: 00007f735e4b46c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000078faa000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lookup_slow+0x28c/0x3f0 fs/namei.c:1718 lookup_slow fs/namei.c:1735 [inline] lookup_one_unlocked+0x1a4/0x290 fs/namei.c:2898 ovl_lookup_positive_unlocked fs/overlayfs/namei.c:210 [inline] ovl_lookup_single+0x200/0xbd0 fs/overlayfs/namei.c:240 ovl_lookup_layer+0x417/0x510 fs/overlayfs/namei.c:333 ovl_lookup+0xcf7/0x2a60 fs/overlayfs/namei.c:1124 lookup_one_qstr_excl+0x11f/0x260 fs/namei.c:1633 filename_create+0x297/0x540 fs/namei.c:3980 do_mknodat+0x18b/0x5b0 fs/namei.c:4125 __do_sys_mknod fs/namei.c:4171 [inline] __se_sys_mknod fs/namei.c:4169 [inline] __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4169 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f735d779ef9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f735e4b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 00007f735d915f80 RCX: 00007f735d779ef9 RDX: 0000000000000700 RSI: 0000000000002000 RDI: 0000000020000140 RBP: 00007f735d7e793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f735d915f80 R15: 00007ffd8cecbb18 Modules linked in: CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc9000492f558 EFLAGS: 00010246 RAX: 1ffffffff17f1868 RBX: ffffffff8bf8c340 RCX: ffff888024845a00 RDX: 0000000000000000 RSI: ffff8880699ead38 RDI: ffff888069bac018 RBP: ffffc9000492f670 R08: ffffffff820c2f53 R09: 1ffffffff29ad1f5 R10: dffffc0000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff8880699ead38 R14: 1ffff1100d33d5a7 R15: 1ffff92000925eb0 FS: 00007f735e4b46c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000078faa000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Tested on: commit: 7d6899fb ovl: fsync after metadata copy-up git tree: git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs.git overlayfs-next console output: https://syzkaller.appspot.com/x/log.txt?x=1272d5b7980000 kernel config: https://syzkaller.appspot.com/x/.config?x=d806687521800cad dashboard link: https://syzkaller.appspot.com/bug?extid=94891a5155abdf6821b7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Note: no patches were applied.