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 59BCFC33CAF for ; Thu, 16 Jan 2020 17:29:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E49F24709 for ; Thu, 16 Jan 2020 17:29:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579195760; bh=gKfMirSXY4Hz5bEhg0xMWQubzmrFf7IxaE0FqOAsBck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WKw2VvQucTXzHpitE49w9emiSyPtzW+r0GTrIjb4L0oDdVWOEhsR2P3W/RJetY8nu uPNb6H647q88i0WWOMiNZbDNPcfi536B3Lqt+T/VzBayjZo2qXGV7qwVgAQbj93nIL TKq+hXIT6sMaiGWtm7CMUiq47jBN2bTldxaeGJLA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391422AbgAPR3S (ORCPT ); Thu, 16 Jan 2020 12:29:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:40904 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404293AbgAPR3L (ORCPT ); Thu, 16 Jan 2020 12:29:11 -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 C5172246F9; Thu, 16 Jan 2020 17:29:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579195751; bh=gKfMirSXY4Hz5bEhg0xMWQubzmrFf7IxaE0FqOAsBck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VT/KicY4iFAk8oq9Wi5GSwO5ctgtxU4sM4qnQFq08pt199uGpq+wIGU1WBrhSK9mn FmtQvSslEpylS/d6LBY/1RRrhAaukwnVH1Ntf0Il9X30DCQmaUc5vvdiHF1Wlgyd1J hkJ0IJuijMdBdaLOcvRO5gHSmgRT9bbDSHiwlTIY= 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 4.14 283/371] staging: greybus: light: fix a couple double frees Date: Thu, 16 Jan 2020 12:22:35 -0500 Message-Id: <20200116172403.18149-226-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116172403.18149-1-sashal@kernel.org> References: <20200116172403.18149-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 0f538b8c3a07..4e7575147775 100644 --- a/drivers/staging/greybus/light.c +++ b/drivers/staging/greybus/light.c @@ -1103,21 +1103,21 @@ 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