From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Date: Sun, 18 Oct 2020 19:17:44 +0000 Subject: [PATCH AUTOSEL 5.9 088/111] fbmem: add margin check to fb_check_caps() Message-Id: <20201018191807.4052726-88-sashal@kernel.org> List-Id: References: <20201018191807.4052726-1-sashal@kernel.org> In-Reply-To: <20201018191807.4052726-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: George Kennedy , syzbot+e5fd3e65515b48c02a30@syzkaller.appspotmail.com, Dan Carpenter , Dhaval Giani , Bartlomiej Zolnierkiewicz , Sasha Levin , linux-fbdev@vger.kernel.org From: George Kennedy [ Upstream commit a49145acfb975d921464b84fe00279f99827d816 ] A fb_ioctl() FBIOPUT_VSCREENINFO call with invalid xres setting or yres setting in struct fb_var_screeninfo will result in a KASAN: vmalloc-out-of-bounds failure in bitfill_aligned() as the margins are being cleared. The margins are cleared in chunks and if the xres setting or yres setting is a value of zero upto the chunk size, the failure will occur. Add a margin check to validate xres and yres settings. Signed-off-by: George Kennedy Reported-by: syzbot+e5fd3e65515b48c02a30@syzkaller.appspotmail.com Reviewed-by: Dan Carpenter Cc: Dhaval Giani Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/1594149963-13801-1-git-send-email-george.kennedy@oracle.com Signed-off-by: Sasha Levin --- drivers/video/fbdev/core/fbmem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 6815bfb7f5724..e33bf1c386926 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1006,6 +1006,10 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var) return 0; } + /* bitfill_aligned() assumes that it's at least 8x8 */ + if (var->xres < 8 || var->yres < 8) + return -EINVAL; + ret = info->fbops->fb_check_var(var, info); if (ret) -- 2.25.1 From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 3A4A5C433DF for ; Sun, 18 Oct 2020 19:55:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F2C2022263 for ; Sun, 18 Oct 2020 19:55:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603050935; bh=7FhvxEzjT00hcJe2A4kMsdfABA3zFVZWm25OuutXf9M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CKPZqWtfAyjqXeOmIgEUg0nHD8f/VlkAxuVx+dKU0XAbxMdSI9dyIp+HY5nPabkwL VP9KJ2Loq/2D1xTc3kCHx7h8kgrKTK3rkc3caYwu08PHqQ1bQ0XYZpodCVfiN6dDv/ PM09Vh5LXHANHm3Y7G6oUpjUEkIYDJ56ZTLbmASM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388281AbgJRTze (ORCPT ); Sun, 18 Oct 2020 15:55:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:58992 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728572AbgJRTTy (ORCPT ); Sun, 18 Oct 2020 15:19:54 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C217F222EC; Sun, 18 Oct 2020 19:19:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603048793; bh=7FhvxEzjT00hcJe2A4kMsdfABA3zFVZWm25OuutXf9M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dyM91xtqZATQCh9yNtKiOFEqQvPl/GINZl3NrowCMWRRkrdJqziIWVAcwBQ+j0lbR +hUjTUW1XxLoUXa7Yf0wBKZfzXPSFNCsDt7kp33Q6u7VmZjufQM7O4Wmju7mNORnjX G2pu7GwlgeAooeTfheJOsg4Ya1AC3AIYTEJKhYrQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: George Kennedy , syzbot+e5fd3e65515b48c02a30@syzkaller.appspotmail.com, Dan Carpenter , Dhaval Giani , Bartlomiej Zolnierkiewicz , Sasha Levin , linux-fbdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.9 088/111] fbmem: add margin check to fb_check_caps() Date: Sun, 18 Oct 2020 15:17:44 -0400 Message-ID: <20201018191807.4052726-88-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201018191807.4052726-1-sashal@kernel.org> References: <20201018191807.4052726-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org Message-ID: <20201018191744.26jnxKToezciVJbn-glNbFfnuFdtBREEF9wiXVDCNYc@z> From: George Kennedy [ Upstream commit a49145acfb975d921464b84fe00279f99827d816 ] A fb_ioctl() FBIOPUT_VSCREENINFO call with invalid xres setting or yres setting in struct fb_var_screeninfo will result in a KASAN: vmalloc-out-of-bounds failure in bitfill_aligned() as the margins are being cleared. The margins are cleared in chunks and if the xres setting or yres setting is a value of zero upto the chunk size, the failure will occur. Add a margin check to validate xres and yres settings. Signed-off-by: George Kennedy Reported-by: syzbot+e5fd3e65515b48c02a30@syzkaller.appspotmail.com Reviewed-by: Dan Carpenter Cc: Dhaval Giani Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/1594149963-13801-1-git-send-email-george.kennedy@oracle.com Signed-off-by: Sasha Levin --- drivers/video/fbdev/core/fbmem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 6815bfb7f5724..e33bf1c386926 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1006,6 +1006,10 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var) return 0; } + /* bitfill_aligned() assumes that it's at least 8x8 */ + if (var->xres < 8 || var->yres < 8) + return -EINVAL; + ret = info->fbops->fb_check_var(var, info); if (ret) -- 2.25.1