From patchwork Thu May 28 05:20:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 225168 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F119EC433E0 for ; Thu, 28 May 2020 05:20:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4194214D8 for ; Thu, 28 May 2020 05:20:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590643253; bh=8F95w6NfYH4Aub7J6ainY1th9ClMvivYnWp8faYCQbE=; h=Date:From:To:Subject:In-Reply-To:List-ID:From; b=Q3QXqHjh3ti37Z7ZHBf6lDQ90BVQciSNr2JD4R99G/VfKY53D1ISczdNptewXkze3 M4fkuakP4vQlUpbv98Ydmre1KmMOwHprI2wZMpcz2w3rtHxWgDNgWLfjhBUOgmy4Bn 95E6EP6yr8K+yNS95DOJFtRfWIuAatM04HP0OW7Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727056AbgE1FUx (ORCPT ); Thu, 28 May 2020 01:20:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:45446 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725764AbgE1FUx (ORCPT ); Thu, 28 May 2020 01:20:53 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A54F4206F1; Thu, 28 May 2020 05:20:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590643253; bh=8F95w6NfYH4Aub7J6ainY1th9ClMvivYnWp8faYCQbE=; h=Date:From:To:Subject:In-Reply-To:From; b=18RgYJlpK+mXG3ym1oOEanuO90hDfkritfzG84ckuzkpQL+2Fe9iO5dS1Z3SIizUj AnMFuzpkOSXQdoeD3ExTdB4RXZI89SSaeLY+s+VS6cO8q1MPNsUZ8TLTe+sNSIac5Y rcLjL1UuDY23JgXLTkXb5cqKr0wmbN+6+g7mcGzI= Date: Wed, 27 May 2020 22:20:52 -0700 From: Andrew Morton To: adobriyan@gmail.com, akpm@linux-foundation.org, glider@google.com, keescook@chromium.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, stable@vger.kernel.org, sunhaoyl@outlook.com, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk Subject: [patch 4/5] fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info() Message-ID: <20200528052052.tLpI_z4pp%akpm@linux-foundation.org> In-Reply-To: <20200527222015.62ba8592af63dae12ab58ffe@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexander Potapenko Subject: fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info() KMSAN reported uninitialized data being written to disk when dumping core. As a result, several kilobytes of kmalloc memory may be written to the core file and then read by a non-privileged user. Link: http://lkml.kernel.org/r/20200419100848.63472-1-glider@google.com Link: https://github.com/google/kmsan/issues/76 Signed-off-by: Alexander Potapenko Reported-by: sam Acked-by: Kees Cook Cc: Al Viro Cc: Alexey Dobriyan Cc: Signed-off-by: Andrew Morton --- fs/binfmt_elf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/binfmt_elf.c~fs-binfmt_elfc-allocate-initialized-memory-in-fill_thread_core_info +++ a/fs/binfmt_elf.c @@ -1733,7 +1733,7 @@ static int fill_thread_core_info(struct (!regset->active || regset->active(t->task, regset) > 0)) { int ret; size_t size = regset_size(t->task, regset); - void *data = kmalloc(size, GFP_KERNEL); + void *data = kzalloc(size, GFP_KERNEL); if (unlikely(!data)) return 0; ret = regset->get(t->task, regset,