From patchwork Thu May 20 09:18:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 444342 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 C7A18C43460 for ; Thu, 20 May 2021 10:16:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A56BD60FE5 for ; Thu, 20 May 2021 10:16:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236577AbhETKR5 (ORCPT ); Thu, 20 May 2021 06:17:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:46918 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235235AbhETKPj (ORCPT ); Thu, 20 May 2021 06:15:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 43921619B8; Thu, 20 May 2021 09:45:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621503954; bh=hs+EqPyCDyqCDKC+REF6QbabERUgprgunsI+jUv/DwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RFqbHFEzFfR2CpGXKPUySFVyXqALPiwxqna4z9/xzMKRmEYhhBLxSf/XDtLhGoKxE RTPR6SthhW8Kf4rJIupSA141KDpEoT0nAZBX/OZopCPlLPBJVeZroi+kQPTWlOQbAF 9ZHCLZmtVWyCPMKxREBtNCmDT/VBaqMhHUVBSIU4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+47fa9c9c648b765305b9@syzkaller.appspotmail.com, Geert Uytterhoeven , Phillip Potter Subject: [PATCH 4.14 029/323] fbdev: zero-fill colormap in fbcmap.c Date: Thu, 20 May 2021 11:18:41 +0200 Message-Id: <20210520092121.110014320@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092120.115153432@linuxfoundation.org> References: <20210520092120.115153432@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Phillip Potter commit 19ab233989d0f7ab1de19a036e247afa4a0a1e9c upstream. Use kzalloc() rather than kmalloc() for the dynamically allocated parts of the colormap in fb_alloc_cmap_gfp, to prevent a leak of random kernel data to userspace under certain circumstances. Fixes a KMSAN-found infoleak bug reported by syzbot at: https://syzkaller.appspot.com/bug?id=741578659feabd108ad9e06696f0c1f2e69c4b6e Reported-by: syzbot+47fa9c9c648b765305b9@syzkaller.appspotmail.com Cc: stable Reviewed-by: Geert Uytterhoeven Signed-off-by: Phillip Potter Link: https://lore.kernel.org/r/20210331220719.1499743-1-phil@philpotter.co.uk Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/core/fbcmap.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/video/fbdev/core/fbcmap.c +++ b/drivers/video/fbdev/core/fbcmap.c @@ -101,17 +101,17 @@ int fb_alloc_cmap_gfp(struct fb_cmap *cm if (!len) return 0; - cmap->red = kmalloc(size, flags); + cmap->red = kzalloc(size, flags); if (!cmap->red) goto fail; - cmap->green = kmalloc(size, flags); + cmap->green = kzalloc(size, flags); if (!cmap->green) goto fail; - cmap->blue = kmalloc(size, flags); + cmap->blue = kzalloc(size, flags); if (!cmap->blue) goto fail; if (transp) { - cmap->transp = kmalloc(size, flags); + cmap->transp = kzalloc(size, flags); if (!cmap->transp) goto fail; } else {