From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) (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 404C760264 for ; Fri, 26 Jan 2024 09:05:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706259931; cv=none; b=HfdwZzSwad1m2jtOR2x96q6tfp4n4+ZxOnrEtzPMDexI75fg/djK4XEU9VvCI3h7l0l0aAlpFTuUKYSyIlN/2omVX6QHPtk4EC2bWO0jwJ3ANViEJlI4Scc6iREROi2q+88ij/c+a2M4M3s2NF8qSVFLByeOt/MZOm0bWAnLiMk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706259931; c=relaxed/simple; bh=T9wpoH0F1cIP8eVCnBQyB/bvSH/l99a66hT/RBmiLG4=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=O389zo94uKQgn60b5okwu9hvloZormcmA2/vYcpXHXfL6qB5lNeC22EM1g9+g/lGmWV+xW4wduHzE0TP6GlM8FJprQ1NDfx5xtPyc3Z3Ji6bGH9FUVD8KF5gWge313m88L76k0dLiBVmWom4RrbGiQsqjZj/IsRfgRJ4kt1w/eo= 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=209.85.166.71 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-f71.google.com with SMTP id ca18e2360f4ac-7bf4698825eso28701939f.0 for ; Fri, 26 Jan 2024 01:05:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706259928; x=1706864728; h=content-transfer-encoding:to:from:subject:message-id:date :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=spc1ShxOmdgB1pC4pVuSbJpCr0hgxztE/zkQiLNA1BA=; b=bCIphzsSQTZZXrnZYCkDaOdXUjDejYIqug8TQfErTnGiLlICjAqn40LU5j2WjmaMhb MWIKsA1i3Mh8u22sKAsICTrDnSTdSeyYOgOz/ct0NBvmbN6lDbeAq6LDwAVPKOd3HkHP 3JpGeJPd61zr4CDxVNQI7PnIfRAhIkicAVz1nQxSi54IwlmrVy1V966EgM9+wS+WPwm7 +9aLBK0w43UC02XEnVMJ1i/sSJJ1w5JGHzw8h9J2mADumNChxLgJHu18MUZS9Wyv0QlF PH7jAzsLjBa7LCocqoBoaZd65RPDZylYFKYtszD6+7MmUhnX4xlILIhwFjEpHBrC/CXy +puw== X-Gm-Message-State: AOJu0Yw4F5mZ1ZrpbakAfix164wmvAMHMoTAQO6YaYRgl098z6TS9PjW nDFXEJEVBOotMTs0Txw7nmkjoBnUjhWRj9foUdkOX55RVqNRnkbVay6n3xKoZB5SNXy5Ujd3B2W K0iGZHNu08a3Es/ckEKI/sfui8ma2PMshBwYrdO7Lt4ysSbyjvKoa+aM= X-Google-Smtp-Source: AGHT+IHkbZUO6XeiPdqbgZ81JcfuzhhS+rfbSkGWl/OfSYFJsF50hYFc2QlOeN4HJWElFBahgMEfpsWHgH1d9zPXSqNXmaddU+mo Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a02:cacd:0:b0:46e:668b:58d7 with SMTP id f13-20020a02cacd000000b0046e668b58d7mr7716jap.0.1706259928470; Fri, 26 Jan 2024 01:05:28 -0800 (PST) Date: Fri, 26 Jan 2024 01:05:28 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000ee5c6c060fd59890@google.com> Subject: [syzbot] [net?] [v9fs?] WARNING: refcount bug in p9_req_put (3) From: syzbot To: asmadeus@codewreck.org, ericvh@kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux_oss@crudebyte.com, lucho@ionkov.net, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, v9fs@lists.linux.dev Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hello, syzbot found the following issue on: HEAD commit: 4fbbed787267 Merge tag 'timers-core-2024-01-21' of git://g.= . git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=3D11bfbdc7e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=3D4059ab9bf06b6ce= b dashboard link: https://syzkaller.appspot.com/bug?extid=3Dd99d2414db66171fc= cbb compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Deb= ian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc= 7510fe41f/non_bootable_disk-4fbbed78.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/13a98041382d/vmlinux-= 4fbbed78.xz kernel image: https://storage.googleapis.com/syzbot-assets/0a02086862ee/bzI= mage-4fbbed78.xz IMPORTANT: if you fix the issue, please add the following tag to the commit= : Reported-by: syzbot+d99d2414db66171fccbb@syzkaller.appspotmail.com 9p: Unknown Cache mode or invalid value fsca=EF=BF=BDhe 9pnet: Tag 65535 still in use ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 3 PID: 30609 at lib/refcount.c:28 refcount_warn_saturate+0x14= a/0x210 lib/refcount.c:28 Modules linked in: CPU: 3 PID: 30609 Comm: syz-executor.1 Not tainted 6.7.0-syzkaller-13004-g4= fbbed787267 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16= .2-1 04/01/2014 RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Code: ff 89 de e8 e8 af 1e fd 84 db 0f 85 66 ff ff ff e8 ab b4 1e fd c6 05 = 1b 87 bb 0a 01 90 48 c7 c7 c0 70 2f 8b e8 97 a9 e4 fc 90 <0f> 0b 90 90 e9 4= 3 ff ff ff e8 88 b4 1e fd 0f b6 1d f6 86 bb 0a 31 RSP: 0018:ffffc9000345f9b0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90006349000 RDX: 0000000000040000 RSI: ffffffff814e1906 RDI: 0000000000000001 RBP: ffff8880687d59a0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffc9000345fa48 R13: ffff8880687d59a0 R14: ffff888026a9d800 R15: 1ffff9200068bf41 FS: 0000000000000000(0000) GS:ffff88802c900000(0063) knlGS:00000000f7ff1b4= 0 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000020003000 CR3: 000000006eb7c000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test include/linux/refcount.h:272 [inline] __refcount_dec_and_test include/linux/refcount.h:304 [inline] refcount_dec_and_test include/linux/refcount.h:322 [inline] p9_req_put+0x1f0/0x250 net/9p/client.c:401 p9_tag_cleanup net/9p/client.c:428 [inline] p9_client_destroy+0x226/0x480 net/9p/client.c:1073 v9fs_session_init+0xba5/0x1a80 fs/9p/v9fs.c:490 v9fs_mount+0xc6/0xcd0 fs/9p/vfs_super.c:123 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8c/0x370 fs/super.c:1784 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x14e6/0x1f20 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x291/0x310 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x79/0x110 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x70/0x7a RIP: 0023:0xf7ff6579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 = 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 9= 0 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7ff15ac EFLAGS: 00000292 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00000000200001c0 RCX: 0000000020000480 RDX: 00000000200004c0 RSI: 0000000000000404 RDI: 0000000020001080 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup