From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7E725166F3D for ; Sun, 29 Sep 2024 13:40:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727617200; cv=none; b=uL3UnbjakWv0jCcPSdFJyJ9MJczBLYHm1XXSvnySpV2lnottwKGFwN74ZdgqOUrZ6YEBoXD4QHldEFQij++Yl7F4BvMliXEfxVL3NIwP9pmgqsSrTvzyVxiNLfH36OdjjwNPHaW9x+A/dDo08cHBeYmL1FCaKa27gWo4wJRjWIE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727617200; c=relaxed/simple; bh=WZNlbBQbwlLCr4ZEDPqAAsWk/TPoLqG4RZo9BD5jahg=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=IUyXd4Xk0njkJ2/PtzN02C6O7QHSe6fs4FL9A5dKXPPS0VjNa5KXX4ijjwtVzo7Pap9um5W0m/eOn4HSf95ARTaDouWyPKsLAKwmnZR5E1s3a0AxdVaXmmkU9VvzEeBTXfOlohlgHlnn4RYmqWL3KS5I5gk1H8KrrtY9R/W5d+8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=V837Ri/R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="V837Ri/R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55D52C4CEC5; Sun, 29 Sep 2024 13:39:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727617200; bh=WZNlbBQbwlLCr4ZEDPqAAsWk/TPoLqG4RZo9BD5jahg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=V837Ri/RAGmZUnf0jM1Ruxel1IvLtoDo928JL6b3Lio1PBU6pWgZF2oqGq9Yqf/xo VtJubZeLa/Yxq9tcmvVSdZAw3ZG51SmwxizZJ2b/8dYXeSnxzMB/jXM6VasQueAMVI NXKIOvYtPtAV25gN3MXd/DYYxKG0UNbpzh46ErCmZ3gftZi5XdZj/8afaX5/OxU/v8 E1VWTsGn4GqlxLgaONrBQVeso3lmTVhejjaxEXC9yEwXzhoompZWKhKIpYnHpEMFeh ARcZXAdDe49G8wXGKQBr8inMaaaaEe5LKTJgwncjmM4B1Op4nrRb8fUM4WXqEEJ8qG zW6I87hVBaXAA== Date: Sun, 29 Sep 2024 22:39:56 +0900 From: Masami Hiramatsu (Google) To: Oleg Nesterov Cc: Peter Zijlstra , Catalin Marinas , "Liao, Chang" , Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH] uprobes: fix kernel info leak via "[uprobes]" vma Message-Id: <20240929223956.5043f74bc781a124e761f013@kernel.org> In-Reply-To: <20240926162901.GA9716@redhat.com> References: <20240926162901.GA9716@redhat.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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-Transfer-Encoding: 7bit On Thu, 26 Sep 2024 18:29:01 +0200 Oleg Nesterov wrote: > xol_add_vma() maps the uninitialized page allocated by __create_xol_area() > into userspace. On some architectures (x86) this memory is readable even > without VM_READ, VM_EXEC results in the same pgprot_t as VM_EXEC|VM_READ. Good catch! I think we push this urgently and send it to stable tree too, right? Fixes: d4b3b6384f98 ("uprobes/core: Allocate XOL slots for uprobes use") Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) Thank you, > Reported-by: Will Deacon > Signed-off-by: Oleg Nesterov > --- > kernel/events/uprobes.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c > index 2ec796e2f055..4b52cb2ae6d6 100644 > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -1545,7 +1545,7 @@ static struct xol_area *__create_xol_area(unsigned long vaddr) > if (!area->bitmap) > goto free_area; > > - area->page = alloc_page(GFP_HIGHUSER); > + area->page = alloc_page(GFP_HIGHUSER | __GFP_ZERO); > if (!area->page) > goto free_bitmap; > > -- > 2.25.1.362.g51ebf55 > > -- Masami Hiramatsu (Google)