Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932747AbbDMTNB (ORCPT ); Mon, 13 Apr 2015 15:13:01 -0400 Received: from mail-ig0-f171.google.com ([209.85.213.171]:36855 "EHLO mail-ig0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932548AbbDMTM7 convert rfc822-to-8bit (ORCPT ); Mon, 13 Apr 2015 15:12:59 -0400 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT From: Michael Turquette User-Agent: alot/0.3.5 To: Rhyland Klein , "Mans Rullgard" , "Stephen Boyd" , linux-kernel@vger.kernel.org References: <1424003629-11383-1-git-send-email-mans@mansr.com> <54E37335.8000305@nvidia.com> In-Reply-To: <54E37335.8000305@nvidia.com> Message-ID: <20150413191250.19585.71603@quantum> Subject: Re: [PATCH] clk: check for invalid parent index of orphans in __clk_init() Date: Mon, 13 Apr 2015 12:12:50 -0700 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2028 Lines: 54 Quoting Rhyland Klein (2015-02-17 08:58:29) > On 2/15/2015 7:33 AM, Mans Rullgard wrote: > > If a mux clock is initialised (by hardware or firmware) with an > > invalid parent, its ->get_parent() can return an out of range > > index. For example, the generic mux clock attempts to return > > -EINVAL, which due to the u8 return type ends up a rather large > > number. Using this index with the parent_names[] array results > > in an invalid pointer and (usually) a crash in the following > > strcmp(). > > > > This patch adds a check for the parent index being in range, > > ignoring clocks reporting invalid values. > > > > Signed-off-by: Mans Rullgard > > Cc: Rhyland Klein > > --- > > drivers/clk/clk.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > > index d48ac71..bc0662b 100644 > > --- a/drivers/clk/clk.c > > +++ b/drivers/clk/clk.c > > @@ -1950,7 +1950,8 @@ int __clk_init(struct device *dev, struct clk *clk) > > hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { > > if (orphan->num_parents && orphan->ops->get_parent) { > > i = orphan->ops->get_parent(orphan->hw); > > - if (!strcmp(clk->name, orphan->parent_names[i])) > > + if (i >= 0 && i < orphan->num_parents && > > + !strcmp(clk->name, orphan->parent_names[i])) > > __clk_reparent(orphan, clk); > > continue; > > } > > > > This works for me and is less invasive than the original patch series. > > Tested-by: Rhyland Klein Applied. Thanks, Mike > > -rhyland > > -- > nvpublic -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/