From patchwork Wed Nov 2 11:01:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 13027970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8BFA7C4167B for ; Wed, 2 Nov 2022 11:02:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230273AbiKBLCY (ORCPT ); Wed, 2 Nov 2022 07:02:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230089AbiKBLCW (ORCPT ); Wed, 2 Nov 2022 07:02:22 -0400 Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [217.70.183.199]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96742222B0; Wed, 2 Nov 2022 04:02:20 -0700 (PDT) Received: from booty.fritz.box (unknown [77.244.183.192]) (Authenticated sender: luca.ceresoli@bootlin.com) by mail.gandi.net (Postfix) with ESMTPA id 21E19FF81A; Wed, 2 Nov 2022 11:02:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1667386936; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=AIWP8hCG3H8802+ZOuJvt5Vl5+0UlGU9wyMe8L68JX0=; b=il6dEg4V1FoLPtn1gLJiTHTPHNENeF9bzb58WJ1zQuz2JTaOA2NIyarOSIrsc3xmXKiCiL Nn1Nn+uwyVC39P7pdBs+56MGUX9ac6tCHwu8QqQQI4vVQ/Cf913yJa28Ve4/J2/8zwSZll xOvQ9/HGzov3hy0WiEwVwTuvgEXKknj1OXO7fDh0+yiyfSWG52xp452qr2s5kCP40MIYpG W/6GNcYmsCaih1/I3yBfG/VnxWgnNrKAm3zUn3/6cSJVgxSh518GIQSU6NSP9guwDSlwZt +8NRQ2dA+nN/hz7oMOZn9HDB0vwiHSvMyYfb4rqltdrpk9ozXIAwKsdHb5wqfA== From: luca.ceresoli@bootlin.com To: Thierry Reding , Jonathan Hunter , Sowjanya Komatineni , Mauro Carvalho Chehab , Greg Kroah-Hartman , Hans Verkuil , Dmitry Osipenko Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-tegra@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, Luca Ceresoli , stable@vger.kernel.org, Dan Carpenter Subject: [PATCH v2 1/2] staging: media: tegra-video: fix chan->mipi value on error Date: Wed, 2 Nov 2022 12:01:01 +0100 Message-Id: <20221102110102.25050-1-luca.ceresoli@bootlin.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Luca Ceresoli chan->mipi takes the return value of tegra_mipi_request() which can be a valid pointer or an error. However chan->mipi is checked in several places, including error-cleanup code in tegra_csi_channels_cleanup(), as 'if (chan->mipi)', which suggests the initial intent was that chan->mipi should be either NULL or a valid pointer, never an error. As a consequence, cleanup code in case of tegra_mipi_request() errors would dereference an invalid pointer. Fix by ensuring chan->mipi always contains either NULL or a void pointer. Also add that to the documentation. Fixes: 523c857e34ce ("media: tegra-video: Add CSI MIPI pads calibration") Cc: stable@vger.kernel.org Reported-by: Dan Carpenter Signed-off-by: Luca Ceresoli --- This patch was added in v2. --- drivers/staging/media/tegra-video/csi.c | 1 + drivers/staging/media/tegra-video/csi.h | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c index b26e44adb2be..6b59ef55c525 100644 --- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -448,6 +448,7 @@ static int tegra_csi_channel_alloc(struct tegra_csi *csi, chan->mipi = tegra_mipi_request(csi->dev, node); if (IS_ERR(chan->mipi)) { ret = PTR_ERR(chan->mipi); + chan->mipi = NULL; dev_err(csi->dev, "failed to get mipi device: %d\n", ret); } diff --git a/drivers/staging/media/tegra-video/csi.h b/drivers/staging/media/tegra-video/csi.h index 4ee05a1785cf..6960ea2e3d36 100644 --- a/drivers/staging/media/tegra-video/csi.h +++ b/drivers/staging/media/tegra-video/csi.h @@ -56,7 +56,7 @@ struct tegra_csi; * @framerate: active framerate for TPG * @h_blank: horizontal blanking for TPG active format * @v_blank: vertical blanking for TPG active format - * @mipi: mipi device for corresponding csi channel pads + * @mipi: mipi device for corresponding csi channel pads, or NULL if not applicable (TPG, error) * @pixel_rate: active pixel rate from the sensor on this channel */ struct tegra_csi_channel { From patchwork Wed Nov 2 11:01:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 13027969 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C03D2C43217 for ; Wed, 2 Nov 2022 11:02:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230302AbiKBLCX (ORCPT ); Wed, 2 Nov 2022 07:02:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230013AbiKBLCW (ORCPT ); Wed, 2 Nov 2022 07:02:22 -0400 Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [217.70.183.199]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D93C1C12F; Wed, 2 Nov 2022 04:02:19 -0700 (PDT) Received: from booty.fritz.box (unknown [77.244.183.192]) (Authenticated sender: luca.ceresoli@bootlin.com) by mail.gandi.net (Postfix) with ESMTPA id E13CDFF81B; Wed, 2 Nov 2022 11:02:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1667386938; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BsVwSyTy7VR6zA7SYC3DsZTfRvN6uc9dyTL1pmSjsKc=; b=S9wMALCHC+8JwGZW0fLzV0Yl0hnE4rD+7X1HlvjAbPHVOE9uzHDWQWMVKB9odDx3QD1cma grde237SUWw9gSJ1zZDAlB7eBlLjo7OGi+MBtMQVd3nIjRL+SZIksNHMxKDyXNzeQGo+eU iU6BmZ2aDzL6ZrkXg2ip3K+pdJg3/SrLG+lr2T5EhhU8aWndjlbfC+uk5jx0Hd1UGRfbRs 6QjHSBOfKvvzuZwAYU0Uov+FEbsrVMORETB2FW3ZW6Hvdku2aEBPNFc6O7eM2gSo7IMpY6 vZ0SICKwlBKnqvrdlQVhP2/zn1TBi0jnMUqgulniY995e1OMxtn12ptSzk29XQ== From: luca.ceresoli@bootlin.com To: Thierry Reding , Jonathan Hunter , Sowjanya Komatineni , Mauro Carvalho Chehab , Greg Kroah-Hartman , Hans Verkuil , Dmitry Osipenko Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-tegra@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, Luca Ceresoli , stable@vger.kernel.org Subject: [PATCH v2 2/2] staging: media: tegra-video: fix device_node use after free Date: Wed, 2 Nov 2022 12:01:02 +0100 Message-Id: <20221102110102.25050-2-luca.ceresoli@bootlin.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221102110102.25050-1-luca.ceresoli@bootlin.com> References: <20221102110102.25050-1-luca.ceresoli@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Luca Ceresoli At probe time this code path is followed: * tegra_csi_init * tegra_csi_channels_alloc * for_each_child_of_node(node, channel) -- iterates over channels * automatically gets 'channel' * tegra_csi_channel_alloc() * saves into chan->of_node a pointer to the channel OF node * automatically gets and puts 'channel' * now the node saved in chan->of_node has refcount 0, can disappear * tegra_csi_channels_init * iterates over channels * tegra_csi_channel_init -- uses chan->of_node After that, chan->of_node keeps storing the node until the device is removed. of_node_get() the node and of_node_put() it during teardown to avoid any risk. Fixes: 1ebaeb09830f ("media: tegra-video: Add support for external sensor capture") Cc: stable@vger.kernel.org Cc: Sowjanya Komatineni Signed-off-by: Luca Ceresoli --- No changes in v2. --- drivers/staging/media/tegra-video/csi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c index 6b59ef55c525..426e653bd55d 100644 --- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -433,7 +433,7 @@ static int tegra_csi_channel_alloc(struct tegra_csi *csi, for (i = 0; i < chan->numgangports; i++) chan->csi_port_nums[i] = port_num + i * CSI_PORTS_PER_BRICK; - chan->of_node = node; + chan->of_node = of_node_get(node); chan->numpads = num_pads; if (num_pads & 0x2) { chan->pads[0].flags = MEDIA_PAD_FL_SINK; @@ -641,6 +641,7 @@ static void tegra_csi_channels_cleanup(struct tegra_csi *csi) media_entity_cleanup(&subdev->entity); } + of_node_put(chan->of_node); list_del(&chan->list); kfree(chan); }