From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932571AbbA0MUW (ORCPT ); Tue, 27 Jan 2015 07:20:22 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:35469 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758748AbbA0MUO (ORCPT ); Tue, 27 Jan 2015 07:20:14 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Tomeu Vizoso , Michael Turquette , Luis Henriques Subject: [PATCH 3.16.y-ckt 119/126] clk: Don't try to use a struct clk* after it could have been freed Date: Tue, 27 Jan 2015 12:17:04 +0000 Message-Id: <1422361031-19364-120-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1422361031-19364-1-git-send-email-luis.henriques@canonical.com> References: <1422361031-19364-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt5 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Tomeu Vizoso commit 10cdfe54dab034311c8e2fad9ba2dffbe616caa9 upstream. As __clk_release could call kfree on clk and then we wouldn't have a safe way of getting the module that owns the clock. Signed-off-by: Tomeu Vizoso Fixes: fcb0ee6a3d33 ("clk: Implement clk_unregister") Reviewed-by: Stephen Boyd Signed-off-by: Michael Turquette Signed-off-by: Luis Henriques --- drivers/clk/clk.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 4cc83ef7ef61..1dee8d2086fb 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2234,14 +2234,17 @@ int __clk_get(struct clk *clk) void __clk_put(struct clk *clk) { + struct module *owner; + if (!clk || WARN_ON_ONCE(IS_ERR(clk))) return; clk_prepare_lock(); + owner = clk->owner; kref_put(&clk->ref, __clk_release); clk_prepare_unlock(); - module_put(clk->owner); + module_put(owner); } /*** clk rate change notifiers ***/ -- 2.1.4