[3.19.y-ckt stable] Patch "clk: ti: dra7-atl-clock: Fix possible ERR_PTR dereference" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    clk: ti: dra7-atl-clock: Fix possible ERR_PTR dereference

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.y-ckt4.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From b35bf0901420882a1bb1034835d84e6a659f7af9 Mon Sep 17 00:00:00 2001
From: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Date: Wed, 13 May 2015 15:54:40 +0900
Subject: clk: ti: dra7-atl-clock: Fix possible ERR_PTR dereference

commit e0cdcda508f110b7ec190dc7c5eb2869ba73a535 upstream.

of_clk_get_from_provider() returns ERR_PTR on failure. The
dra7-atl-clock driver was not checking its return value and
immediately used it in __clk_get_hw().  __clk_get_hw()
dereferences supplied clock, if it is not NULL, so in that case
it would dereference an ERR_PTR.

Fixes: 9ac33b0ce81f ("CLK: TI: Driver for DRA7 ATL (Audio Tracking Logic)")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/clk/ti/clk-dra7-atl.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/clk/ti/clk-dra7-atl.c b/drivers/clk/ti/clk-dra7-atl.c
index 59bb4b3..e14b847 100644
--- a/drivers/clk/ti/clk-dra7-atl.c
+++ b/drivers/clk/ti/clk-dra7-atl.c
@@ -252,6 +252,11 @@ static int of_dra7_atl_clk_probe(struct platform_device *pdev)
 		}

 		clk = of_clk_get_from_provider(&clkspec);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to get atl clock %d from provider\n",
+			       __func__, i);
+			return PTR_ERR(clk);
+		}

 		cdesc = to_atl_desc(__clk_get_hw(clk));
 		cdesc->cinfo = cinfo;
--
1.9.1