From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D3A3521ADC7; Sun, 31 May 2026 19:01:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780254076; cv=none; b=T6nqHvACEiCmjKztD7ijRmd8cmlCkC5XcjY/PmPUMH1D6hfDB+ORJKnFW1m7AFPMsCnA2a6vOpqoxSF2tuWgz+InV8TUsXv4hvgnOqv2WTk00VbQLH+rIAw88bbPgjtVEjHY5lOyc02i8d73k8GH9OdLkrvWsCIQQA6HCE81BCk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780254076; c=relaxed/simple; bh=c6HVtj1BrNeQP8HJB4VgikCUxQBGGOr8yQg/LtHBzKI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YCP1AcirEMDgiTBHyOPvWOAhgc0NAV85lcmrvFVhExaQX8DIYmD5d8daV54YYk9PvjO9ikt6f9GfT8mAwTrY2p+EhyVxrJRgDKIVE087ELgxnvubB36ckRjRhLk7ZV+RSif5ZNJyixORXOljHKt+6KRxrXJ24wlP3ueib5JyRvI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IR3X1VQ3; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IR3X1VQ3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 568961F00893; Sun, 31 May 2026 19:01:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780254075; bh=fcdMJCvYcrxynpav12XOXRlTlPDIl3/7C5MgYt6/rxM=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=IR3X1VQ3sfK8nwizv/o40dv7x4UY52RwB32eTAzN6vkUjJen1CO+9kUOt76HB0+xD iykOW4+TrFC5n9TXfXZXtvSDoJ4ycLBnff42d5ofdKUqncVr1sayrtVj0RNfWKbJU2 Tcbhu2r/7h/Y6zlcnS56zEIybxwmlYZXlD2hhVKlYta+WHVbTe0y4D/eZeHvVWKp00 NFuTbY3VnbUD74bfNyrUJtoXbuONXsBl+I1+jvo3g0GUZcmsHQYkUePajF8NZrvxr3 2nW6ksVuhtD3SjQi/lFyT0qTOGpPU82KdOPIe3G2NUq68rkk9r8Elc8gOHPPplMtq/ vXK2p3JnBERXQ== Message-ID: <6dfa5f7c-ffbd-4605-96f2-09e365ce57dd@kernel.org> Date: Sun, 31 May 2026 21:01:10 +0200 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/3] vmsplice: make vmsplice a trivial wrapper for preadv2/pwritev2 To: Pedro Falcato , Askar Safin Cc: linux-fsdevel@vger.kernel.org, Christian Brauner , Alexander Viro , Jan Kara , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, netdev@vger.kernel.org, Linus Torvalds , Matthew Wilcox , Jens Axboe , Christoph Hellwig , David Howells , Andrew Morton , Miklos Szeredi , patches@lists.linux.dev References: <20260531010107.1953702-1-safinaskar@gmail.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/31/26 10:54, Pedro Falcato wrote: > On Sun, May 31, 2026 at 01:01:04AM +0000, Askar Safin wrote: >> This patchset is for VFS. >> >> Recently we got a lot of vulnerabilities in splice/vmsplice. >> >> Also vmsplice already was source of vulnerabilities in the past: >> CVE-2020-29374 (see https://lwn.net/Articles/849638/ ). >> >> Also vmsplice is problematic for other reasons. Here is what other >> developers say: >> >> Linus Torvalds in 2023: >>> So I'd personally be perfectly ok with just making vmsplice() be >>> exactly the same as write, and turn all of vmsplice() into just "it's >>> a read() if the pipe is open for read, and a write if it's open for >>> writing". >> https://lore.kernel.org/all/CAHk-=wgG_2cmHgZwKjydi7=iimyHyN8aessnbM9XQ9ufbaUz9g@mail.gmail.com/ >> >> Christoph Hellwig in May 2026: >>> vmsplice is the worst, as it is one of the few remaining places that >>> can incorrectly dirty file backed pages without telling the file system >>> and cause the other problems fixed by a FOLL_PIN conversion, but it is >>> the only one where we do not have any idea yet how we could convert it >>> to FOLL_PIN due to the unbounded pin time. >> https://lore.kernel.org/all/agwFlBKvKytjURDO@infradead.org/ >> >> See recent discussion here: >> https://lore.kernel.org/all/20260516182126.530498-1-pfalcato@suse.de/T/#u > > So, you took an ongoing discussion with an ongoing RFC patchset, and you > decided to reimplement part of the idea on your own, as a concurrent patchset. > > Riiiiiight.... I don't think I have to NAK this, do I? Jup. I'll just ignore this patch set here. -- Cheers, David