From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f77.google.com (mail-ot1-f77.google.com [209.85.210.77]) (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 6F3F52853F2 for ; Mon, 29 Dec 2025 11:09:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767006563; cv=none; b=lhOyqE/zBlPH5OrjH3HVkqS8JY9t5dZUpU5U2MuDzvglSK7XRTuZ3D4gG0j4MHZd9ZZBiGHDlDE0taocNF355DVeXSS+ZfaUHNYxNIzKgpS+lpTEgIALtv/lo2JZfKpc4uXmHZ5+APZ9qB5ndMGa6fZ/kgLk3Rvqn4D2pl1oT6Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767006563; c=relaxed/simple; bh=zF7dMigOpvwftBQqWlTRuaCScZVOhHyo89ZvzcMAirg=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=DDBM8sSBntUizvuMR4vUxeaR61szg85xWBKWIPpYIySKSresSvpLgBUHNMw2xj6nIm4t7iwsIvDM7jvk9VBNk/VIEmoYZw3SHpH6MqlYuSKt5RKc7DtofSm+XM7ptdSGCvVSM+2VoRZYGrKMcWogUZM36gUbapxEe+qN7IsyqVw= 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=209.85.210.77 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-ot1-f77.google.com with SMTP id 46e09a7af769-7ce031c61ccso674077a34.0 for ; Mon, 29 Dec 2025 03:09:21 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767006560; x=1767611360; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=8h7ot2e/pevgjJhpsXlySYFFAyGSeroK84z95KyTt1E=; b=T4dIMFqAfxdeBBwcdhGFDeaLAKsFYYraGoDfqB+hpiamR/Km3FwISb42/NlVqFDYJn lD1a6v6c57GBaBtvVfxhc5CYHh0Zp/Vhxo8oOp/VT1A7WC5w+twh0AX2esNil/gH03an XIdBpKcD/M5DaZ+K8JXQOSg4CF9zsj91k7rt2S90EO3S9PdBlbDzP3Ey+lTHOy4vHg+R R/+Vqi8Syak6gMLLa3yK+1svZsJa7grSrQpItq+y38OmTGi7HtNOKlBPVqZd7hQmfRGN f7l4Hn440STsM2j07BHz26Z9p9/HZeJAPt6L4s4dCSRvpSlEfn5tpg5EXEZqf/BXvy/u fZNw== X-Forwarded-Encrypted: i=1; AJvYcCWhjifM/dZknDz0Fwz6VQIqOVyHCBfn1auTYiG8ScPLgHbUjedK8k1GyBjwiBXgBGcTWx1PJ003sqUlXG0=@vger.kernel.org X-Gm-Message-State: AOJu0YyAEqiWRSBZYS2ZuOW1aXFclq7XAwzIvAP1EsyFNhq7XQBflA5e 8aiOu4eRcYt6kxvrlDq7+xUkrDI9twwq1rtO/+c+0Ak6r+VhW6KNXSdocfDWVTdr+X65Prf0DQ4 EIh818jl/WwjBZ89slN0dt3nZTR5KizRf8hkODuMsqq5TTq26Z2MU9KtNuak= X-Google-Smtp-Source: AGHT+IGN+y2PmobodtjcjD0/btZkR+NBWBQkwG1hAMAlafJLjlGYEuuGit4WkQVMj7gZonCMfO2sSBj+WcEzWoLO4k2oz5p8sU5O Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4088:b0:659:9a49:8e26 with SMTP id 006d021491bc7-65cfe748a32mr14373545eaf.24.1767006560351; Mon, 29 Dec 2025 03:09:20 -0800 (PST) Date: Mon, 29 Dec 2025 03:09:20 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69526160.050a0220.3b1790.0005.GAE@google.com> Subject: [syzbot] [fs?] WARNING in put_mnt_ns From: syzbot To: brauner@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 2666975a8905 Add linux-next specific files for 20251111 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16d38914580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e82ba9dc816af74c dashboard link: https://syzkaller.appspot.com/bug?extid=d3005b4273499e174172 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/26ac789d9bdd/disk-2666975a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/fabfe7978a23/vmlinux-2666975a.xz kernel image: https://storage.googleapis.com/syzbot-assets/82f010d50b37/bzImage-2666975a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d3005b4273499e174172@syzkaller.appspotmail.com ------------[ cut here ]------------ WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#0: syz.1.878/9177 WARNING: ./include/linux/ns_common.h:255 at put_mnt_ns+0x152/0x190 fs/namespace.c:6048, CPU#0: syz.1.878/9177 Modules linked in: CPU: 0 UID: 0 PID: 9177 Comm: syz.1.878 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__ns_ref_put include/linux/ns_common.h:255 [inline] RIP: 0010:put_mnt_ns+0x152/0x190 fs/namespace.c:6048 Code: 79 00 00 bf 01 00 00 00 89 ee e8 99 15 7e ff 85 ed 7e 1f e8 50 11 7e ff 5b 41 5e 41 5f 5d c3 cc cc cc cc cc e8 3f 11 7e ff 90 <0f> 0b 90 e9 33 ff ff ff e8 31 11 7e ff 4c 89 f7 be 03 00 00 00 5b RSP: 0018:ffffc900038bfaa8 EFLAGS: 00010293 RAX: ffffffff82434e41 RBX: ffff88807a516000 RCX: ffff88807ce9bd00 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 RBP: 00000000ffffffff R08: ffff88807a5160bb R09: 1ffff1100f4a2c17 R10: dffffc0000000000 R11: ffffed100f4a2c18 R12: dffffc0000000000 R13: 0000000000000009 R14: ffff88807a5160b8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125a82000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc52318fb8 CR3: 0000000030cb8000 CR4: 00000000003526f0 Call Trace: free_nsproxy+0x46/0x560 kernel/nsproxy.c:192 do_exit+0x6b8/0x2300 kernel/exit.c:969 do_group_exit+0x21c/0x2d0 kernel/exit.c:1111 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x171/0x640 kernel/entry/common.c:196 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7ff8b0654d64 Code: Unable to access opcode bytes at 0x7ff8b0654d3a. RSP: 002b:00007ff8b15f2ff0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007ff8b09e6090 RCX: 00007ff8b078f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ff8b0811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff8b09e6128 R14: 00007ff8b09e6090 R15: 00007ffc5231c618 --- 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. 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