From patchwork Thu May 2 06:25:27 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ambresh K X-Patchwork-Id: 2510241 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) by patchwork1.kernel.org (Postfix) with ESMTP id 4C4893FD85 for ; Thu, 2 May 2013 06:26:32 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXmy8-0001ZT-09; Thu, 02 May 2013 06:26:16 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXmxy-0001qp-I3; Thu, 02 May 2013 06:26:06 +0000 Received: from bear.ext.ti.com ([192.94.94.41]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXmxt-0001pU-NL for linux-arm-kernel@lists.infradead.org; Thu, 02 May 2013 06:26:03 +0000 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id r426PdLX030960; Thu, 2 May 2013 01:25:39 -0500 Received: from DFLE73.ent.ti.com (dfle73.ent.ti.com [128.247.5.110]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id r426Pda8030997; Thu, 2 May 2013 01:25:39 -0500 Received: from dlelxv23.itg.ti.com (172.17.1.198) by DFLE73.ent.ti.com (128.247.5.110) with Microsoft SMTP Server id 14.2.342.3; Thu, 2 May 2013 01:25:38 -0500 Received: from legion.dal.design.ti.com (legion.dal.design.ti.com [128.247.22.53]) by dlelxv23.itg.ti.com (8.13.8/8.13.8) with ESMTP id r426PdcX028028; Thu, 2 May 2013 01:25:39 -0500 Received: from localhost (h83-1.vpn.ti.com [172.24.83.1]) by legion.dal.design.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id r426PZV17787; Thu, 2 May 2013 01:25:35 -0500 (CDT) From: Ambresh K To: Mike Turquette Subject: [Patch 1/3] clk: fix clk_mux_get_parent return's signed value Date: Thu, 2 May 2013 11:55:27 +0530 Message-ID: <1367475929-32166-2-git-send-email-ambresh@ti.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1367475929-32166-1-git-send-email-ambresh@ti.com> References: <1367475929-32166-1-git-send-email-ambresh@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130502_022601_932152_61418E82 X-CRM114-Status: GOOD ( 16.18 ) X-Spam-Score: -9.5 (---------) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-9.5 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [192.94.94.41 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -2.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Nishanth Menon , Rajendra , linux-kernel@vger.kernel.org, Tero Kristo , Ambresh K , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Ambresh K If for some reason, the value read from clksel field return erroneous due to HW bug or improper configuration, then clk_mux_get_parent should return appropriate error's. Currently if the value read is greater than the number of available parents clk_mux_get_parent return's signed error which will result in NULL pointer dereferencing in the calling functions. Signed-off-by: Ambresh K --- drivers/clk/clk-mux.c | 2 +- drivers/clk/clk.c | 12 +++++++++++- include/linux/clk-provider.h | 4 ++-- 3 files changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c index 25b1734..be0857e 100644 --- a/drivers/clk/clk-mux.c +++ b/drivers/clk/clk-mux.c @@ -29,7 +29,7 @@ #define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw) -static u8 clk_mux_get_parent(struct clk_hw *hw) +static int clk_mux_get_parent(struct clk_hw *hw) { struct clk_mux *mux = to_clk_mux(hw); int num_parents = __clk_get_num_parents(hw->clk); diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 934cfd1..c187321 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1281,7 +1281,7 @@ EXPORT_SYMBOL_GPL(clk_get_parent); static struct clk *__clk_init_parent(struct clk *clk) { struct clk *ret = NULL; - u8 index; + int index; /* handle the trivial cases */ @@ -1309,6 +1309,11 @@ static struct clk *__clk_init_parent(struct clk *clk) */ index = clk->ops->get_parent(clk->hw); + if (index < 0) { + pr_err("%s: clk(%s) invalid parent clk_sel index(%d)\n", + __func__, clk->name, index); + goto out; + } if (!clk->parents) clk->parents = @@ -1632,6 +1637,11 @@ int __clk_init(struct device *dev, struct clk *clk) hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { if (orphan->ops->get_parent) { i = orphan->ops->get_parent(orphan->hw); + if (i < 0) { + pr_err("%s: orphan clk(%s) invalid parent\n", + __func__, orphan->name); + continue; + } if (!strcmp(clk->name, orphan->parent_names[i])) __clk_reparent(orphan, clk); continue; diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 1186098..96337a1 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -80,7 +80,7 @@ struct clk_hw; * supported by the clock. * * @get_parent: Queries the hardware to determine the parent of a clock. The - * return value is a u8 which specifies the index corresponding to + * return value which specifies the index corresponding to * the parent clock. This index can be applied to either the * .parent_names or .parents arrays. In short, this function * translates the parent value read from hardware into an array @@ -127,7 +127,7 @@ struct clk_ops { long (*round_rate)(struct clk_hw *hw, unsigned long, unsigned long *); int (*set_parent)(struct clk_hw *hw, u8 index); - u8 (*get_parent)(struct clk_hw *hw); + int (*get_parent)(struct clk_hw *hw); int (*set_rate)(struct clk_hw *hw, unsigned long, unsigned long); void (*init)(struct clk_hw *hw);