From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 6D83E72600; Mon, 14 Jul 2025 08:30:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752481839; cv=none; b=TGGbn+2AeCDxo218Ro/cFIt9RsFIb+FIUJRVa5+BiwptMGThrwXljMRM5hAVuVXBWI1EQzeGa7XMKQYXJYiI7HKqcqSbpGf4HI+lBkGvJO1fTe05gn3zLzCsczrPb4VkCB/bQfILpFqzgKaRzlXf8sfBIr0j2oMQaBBkKIDFHBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752481839; c=relaxed/simple; bh=UXxWUo53aedqVB8S2fdgJLytsMH1oCAccK6tpYkBahQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oswLCqRe0RSxImNPRuE34l3ieTY1BmNU0EiSkNBAZIzyiLqHnX1tGs4ONJqNet2V9Tdz8FgM3VCY/2+B7PEEnXN6i0lHtmqWGIccZC9dVM4s2TUpjR/Nfw4Iar42w3wyxRIMH9oGyLF6EIloELhTlx56Cev83rSBGaYxHvIfeMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=N82ZdbCj; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="N82ZdbCj" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=UXxWUo53aedqVB8S2fdgJLytsMH1oCAccK6tpYkBahQ=; b=N82ZdbCjturlES3ex0s4qZ5ELi ZRYcC79RYeThJxke0T2vwa75bcTjUhvtnhO/iTRQBa0UEFVir4P28IRmwZjUTwZiLsO1SVwImeHuF 7hFlHsXyJbMfMH52l02zK2/L8fcKcPWp/2Q6sg/B7t7+MJN7BKIc/1a4NgUO4O1RICAoDEr7QBXGq To19P7TLya59FIblwm/L4zJeOouCEbITe3Ki+9Jvcdp9MecnGA0AXbt1wKiEKa8DBcHwq8itpAFsq yWu9MpCNRaBTHmgbYJDM18xKzGMHXkH4kqGZzvJslNwijPsDmPR1Mg9nDOUOSSq96hCWW9mj0EjJ5 r8sWX5MQ==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1ubEZs-00000006WXJ-025b; Mon, 14 Jul 2025 08:30:24 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id AFF7B300186; Mon, 14 Jul 2025 10:30:22 +0200 (CEST) Date: Mon, 14 Jul 2025 10:30:22 +0200 From: Peter Zijlstra To: Matt Gilbride Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Andrii Nakryiko , David Hildenbrand Subject: Re: [PATCH 1/1] uprobes: relax valid_vma check for VM_MAYSHARE Message-ID: <20250714083022.GJ905792@noisy.programming.kicks-ass.net> References: <20250711200705.1545447-1-mattgilbride@google.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250711200705.1545447-1-mattgilbride@google.com> On Fri, Jul 11, 2025 at 08:07:05PM +0000, Matt Gilbride wrote: > ART maps a memfd twice, once as RW and once as RX, to uphold W^X for > security (defense in depth), I'll argue this is no defence at all. As long as there is a writable mapping for an executable page, you've lost. You have effectively violated W^X.