From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f45.google.com (mail-ej1-f45.google.com [209.85.218.45]) (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 3E1B47EEE6 for ; Fri, 22 Mar 2024 19:46:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.45 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711136816; cv=none; b=CbmKc9hEaxFJZOBXb5jlQtRgErD5ml98YGIwjPXmgY+cMPgiILmMvr+Xsi0j/D1RA8nh79Sf7cI+puEDa/9pisnxRvnzVvIt62bHGIQ7S1lSfHtxQy1E5zPCmOmix3+4r6gorqAcKGo91pG8Fr94hr3ctCO6Ofv5tKbPQOqSB/E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711136816; c=relaxed/simple; bh=U7eZoHi3uHnPeiiWjIrWr64IsGQF0wptDk5u+PKR+OI=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=tKBOKglb7Mjy3QuCbvY7Fh3SQbvoEAhHR+xDZmfGPPSTxpyWAzx0fBgBOadApGAAJqyjSAEecs3bUQzEAvV5kchUkhpSFDWsec0XYNWZnHoIjyoCjORPMSY3D9K7RrCoKC9Zuu9/RgYUg7TSMghVxzXBGudtJB9BqIJr1g3ucWI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=szeredi.hu; spf=pass smtp.mailfrom=szeredi.hu; dkim=pass (1024-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b=nwxJph4F; arc=none smtp.client-ip=209.85.218.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=szeredi.hu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=szeredi.hu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b="nwxJph4F" Received: by mail-ej1-f45.google.com with SMTP id a640c23a62f3a-a466e53f8c0so350772066b.1 for ; Fri, 22 Mar 2024 12:46:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; t=1711136812; x=1711741612; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=DgSSYjlN4+EDU0hEA5qrEbHHQ7GX2ErZACZlkqCEZ+A=; b=nwxJph4Fk6QUjHMrTgATgnSKHU4KRBy7OYgOHhNLs+7PilnlqKXB+OiIb91nwi5gfT bGHaR4cSw9nFKtOi9fbEuqHUQrUG9n6gOC6SnR19OAiN8FH6qReffoz/p1UgFC0DAW0Z Q6d4vl0gK3xMEU0+t9Hst138AR7M58qhy0LwM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711136812; x=1711741612; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=DgSSYjlN4+EDU0hEA5qrEbHHQ7GX2ErZACZlkqCEZ+A=; b=s7rI0ppLcmlLPtTD6WQLcNnYHcvYAhXIrt7UquleuCHz4DxfRSCctVXDbw2UVefdRb 7AF42sfbBQZeuJo0tGUnFa/znkeZ2y0NiI98xPc1SwfGV66F1hk+vrf4FIBxSd4zidyz tzyjEbdxWybkjDpawJXGVuidVK9ViGJgfgnRQmibW+qTzfM2qFUVZxhwAfng89ct27Xx p62lZp4Je0F+674bCLjZplD2cmVF9Ej+OEOGXmA4Ju0pMd8NftvEdbIgBgX/BoDydyRy HvYVMXzofaWUHEG+D41vDOd6Uz+sXtmNwsyhfyzqQcMeBQsOgYOyUmDwfiRHvfVMcBUw S+3A== X-Forwarded-Encrypted: i=1; AJvYcCVXw1ZKwP0JxK2xDYugwQgXeoghhIaTN6KXf0Yx6ZE9+Uo6igWBeaVqkBWj76S74E9303v5qUy5Y9oTPCUtnuAtJcsnIIMlqwk+jlD6 X-Gm-Message-State: AOJu0YwzSiQvCXhmS+XHOkc+p83KeZVcOZhjT80TeUHm+z/cmTp0pWhs bPMIyHUV41fiKQBlnQyJwOrHsy9lFGm9Mvc+9RR9/3QEd6fv7fC1/cOEmRmbcW2pNBDo0gI1r+Y 93hFUNz1IOnuBSBIjK7tiTYV670RdVi4CL0HbLQ== X-Google-Smtp-Source: AGHT+IG+hLVuzSz1xNzlyW3HKUHdwEY6Nk4mkZw/FiNiVTqnWPqumkuOIWEw3KgJCkSCJ8+TFRk6s8gjzxX68YelxYk= X-Received: by 2002:a17:906:61a:b0:a46:5f04:134 with SMTP id s26-20020a170906061a00b00a465f040134mr512071ejb.70.1711136812445; Fri, 22 Mar 2024 12:46:52 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: In-Reply-To: From: Miklos Szeredi Date: Fri, 22 Mar 2024 20:46:40 +0100 Message-ID: Subject: Re: BUG: unable to handle kernel paging request in fuse_copy_do To: David Hildenbrand Cc: xingwei lee , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, samsun1006219@gmail.com, syzkaller-bugs@googlegroups.com, linux-mm , Mike Rapoport Content-Type: text/plain; charset="UTF-8" On Fri, 22 Mar 2024 at 16:41, David Hildenbrand wrote: > But at least the vmsplice() just seems to work. Which is weird, because > GUP-fast should not apply (page not faulted in?) But it is faulted in, and that indeed seems to be the root cause. Improved repro: #define _GNU_SOURCE #include #include #include #include #include #include int main(void) { int fd1, fd2; int pip[2]; struct iovec iov; char *addr; int ret; fd1 = syscall(__NR_memfd_secret, 0); addr = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, fd1, 0); ftruncate(fd1, 7); addr[0] = 1; /* fault in page */ pipe(pip); iov.iov_base = addr; iov.iov_len = 0x50; ret = vmsplice(pip[1], &iov, 1, 0); if (ret == -1 && errno == EFAULT) { printf("Success\n"); return 0; } fd2 = open("/tmp/repro-secretmem.test", O_RDWR | O_CREAT, 0x600); splice(pip[0], NULL, fd2, NULL, 0x50, 0); return 0; }