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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 1A739C33CB7 for ; Thu, 16 Jan 2020 17:41:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9449246CF for ; Thu, 16 Jan 2020 17:41:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196490; bh=SHRQrnJKDSOOsQpXFHmVHP/r6ZAAF9ckpFPKx8D5VNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YJwvo4hbaOfVKG/Z9P/9kw+GfQYeYYg4ePnfJPtGroLR0vIcXDBGfcY5V4/PqgGlb zsZFiehMywB/saVsve/o0dpLqxSgnh5CS+PIKvNMBTli1hanTDuLs1gwrW5/zqDY34 fJrSnDvEH+RM4Gru8AicWE5iFsO/tYa4idaECesw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405678AbgAPRl2 (ORCPT ); Thu, 16 Jan 2020 12:41:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:57590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390521AbgAPRkZ (ORCPT ); Thu, 16 Jan 2020 12:40:25 -0500 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 C2C5C2470F; Thu, 16 Jan 2020 17:40:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196424; bh=SHRQrnJKDSOOsQpXFHmVHP/r6ZAAF9ckpFPKx8D5VNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=neFmv6hVu/rTSu7ErUgDwzOCU7RLfsMibd5Vme86SqsK7+iHvBK4X894m6n9Rt5HD ScVNcvatJmYGvnIKX20avpRiSl8v+WcTWCb+8ZA7u8IlFMp+MrpC3nPnEwnAzhJUPl 309Yyf4GGzFSpLzMgm1fDYS/WvEsMDXufMDDuBlc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Rui Miguel Silva , Greg Kroah-Hartman , Sasha Levin , greybus-dev@lists.linaro.org, devel@driverdev.osuosl.org Subject: [PATCH AUTOSEL 4.9 193/251] staging: greybus: light: fix a couple double frees Date: Thu, 16 Jan 2020 12:35:42 -0500 Message-Id: <20200116173641.22137-153-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116173641.22137-1-sashal@kernel.org> References: <20200116173641.22137-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter [ Upstream commit 329101244f214952606359d254ae883b7109e1a5 ] The problem is in gb_lights_request_handler(). If we get a request to change the config then we release the light with gb_lights_light_release() and re-allocated it. However, if the allocation fails part way through then we call gb_lights_light_release() again. This can lead to a couple different double frees where we haven't cleared out the original values: gb_lights_light_v4l2_unregister(light); ... kfree(light->channels); kfree(light->name); I also made a small change to how we set "light->channels_count = 0;". The original code handled this part fine and did not cause a use after free but it was sort of complicated to read. Fixes: 2870b52bae4c ("greybus: lights: add lights implementation") Signed-off-by: Dan Carpenter Acked-by: Rui Miguel Silva Link: https://lore.kernel.org/r/20190829122839.GA20116@mwanda Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/staging/greybus/light.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c index 9f01427f35f9..1cb82cc28aa7 100644 --- a/drivers/staging/greybus/light.c +++ b/drivers/staging/greybus/light.c @@ -1102,21 +1102,21 @@ static void gb_lights_channel_release(struct gb_channel *channel) static void gb_lights_light_release(struct gb_light *light) { int i; - int count; light->ready = false; - count = light->channels_count; - if (light->has_flash) gb_lights_light_v4l2_unregister(light); + light->has_flash = false; - for (i = 0; i < count; i++) { + for (i = 0; i < light->channels_count; i++) gb_lights_channel_release(&light->channels[i]); - light->channels_count--; - } + light->channels_count = 0; + kfree(light->channels); + light->channels = NULL; kfree(light->name); + light->name = NULL; } static void gb_lights_release(struct gb_lights *glights) -- 2.20.1