From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (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 703A636C; Sat, 4 Jan 2025 00:04:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735949053; cv=none; b=iyPWauxDEXG4oXgYkqKd8KWKmteXSSioGX04jFBzEQbX/4iNTWPqsFAw2rgcy8ldbAJwo0ZAIvnPjpp4QybKCNQD8U6qieZQbfQH29+ce/wOwNFX/nu+dsDCEy47mNg1DQcmFr8A5RZ8ueaCckW6y2Wi4gQ4XvN44ovofjUbyqk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735949053; c=relaxed/simple; bh=Yy++yQU15UJak0FuUUPzCKeuieQdmhTX/GEkQwQJS5o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qlkSpXM7ebaQLMuJ8UAE6Ll1bfxHdWgP/GDCEBUB0cSNtf0lPmiJOeo2GX9pLaOoG+9bktmjM9mZ6C61EjHqQfaChcHWbT7SNFhPInTfEooI1UjuAm/kOvHklMycjlKcUlO2YIprWaFK2w6xcGwLe24cJNwnvFCwFlk9cis9BEI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=pcsEFWZ8; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="pcsEFWZ8" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=KhgMglCFXQO4QMPJMWxdpuWJUo3MEmsC6qyW1d13b0E=; b=pcsEFWZ8AG17xPc1KtJaamACaH ej0smnjBTeKivYKWPQpq/Xu9Zsb3tidmZd74Lsig47wt04b8DeEOdRY4ZBtnzq3BPbkgWPfthNnDL 5k6Zi4iGp2XC1GqomDROvCilnim6DsN8T9HEISE2tyR8LlelDVs56aZAFTEs8euM/HH7x1IlI6c0l NiPegODVHvQR3jgc502lA5PmPPQGFOcr2yuTtKN1d6CBk87XLGXjaZYlS9HPHRXUCJ8+eamJ0r/TV foGvfCjxsUA7GQXiZ1LXTtfeb5550FuHrZYUl5QK1NNEMIdGRhyS9gLcIZK/xSUCr7vlfkZEuFrnK miWX1o/g==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.98 #2 (Red Hat Linux)) id 1tTreC-0000000FE4G-1CrK; Sat, 04 Jan 2025 00:04:08 +0000 Date: Sat, 4 Jan 2025 00:04:08 +0000 From: Al Viro To: cheung wall Cc: Christian Brauner , Jan Kara , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: "INFO: rcu detected stall in sys_sendfile64" in Linux kernel version 6.13.0-rc2 Message-ID: <20250104000408.GE1977892@ZenIV> References: Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Al Viro On Fri, Jan 03, 2025 at 04:20:28PM +0800, cheung wall wrote: > Hello, > > I am writing to report a potential vulnerability identified in the > Linux Kernel version 6.13.0-rc2. This issue was discovered using our > custom vulnerability discovery tool. > > HEAD commit: fac04efc5c793dccbd07e2d59af9f90b7fc0dca4 (tag: v6.13-rc2) > > Detailed Call Stack: > > ------------[ cut here begin]------------ Ugh... Your tool is, by the look of it, some kind of fuzzer. If that is correct, you really need to do a lot of things for it to be useful. "Something done by my userland code has ended up with this spew into kernel log" _may_ be of use in some cases, but examples you've posted are not of that sort. The things missing: * what _was_ done by the userland to trigger that? * how reproducible it is? * which commit (if any) has introduced that behaviour? Might or might not be available, but "bump the version number to 6.13-rc2" is very unlikely to be it. * can the reproducer (if available) be trimmed down? You really would be better off if you described what that tool is trying to do and what are your plans for it - missing parts, etc. As it is, you are dumping a stream of low-quality output on people who are not in position to do anything useful with it. In effect, you are training everyone to ignore anything you post, which is probably not the desired result.