Patch "coresight: checking for NULL string in coresight_name_match()" has been added to the 4.4-stable tree

Patch "coresight: checking for NULL string in coresight_name_match()" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    coresight: checking for NULL string in coresight_name_match()

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     coresight-checking-for-null-string-in-coresight_name_match.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From fadf3a44e974b030e7145218ad1ab25e3ef91738 Mon Sep 17 00:00:00 2001
From: Mathieu Poirier <mathieu.poirier@linaro.org>
Date: Thu, 17 Dec 2015 08:47:02 -0700
Subject: coresight: checking for NULL string in coresight_name_match()

From: Mathieu Poirier <mathieu.poirier@linaro.org>

commit fadf3a44e974b030e7145218ad1ab25e3ef91738 upstream.

Connection child names associated to ports can sometimes be NULL,
which is the case when booting a system on QEMU or when the Coresight
power domain isn't switched on.

This patch is adding a check to make sure a NULL string isn't fed
to strcmp(), something that avoid crashing the system.

Reported-by: Tyler Baker <tyler.baker@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/hwtracing/coresight/coresight.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -548,7 +548,7 @@ static int coresight_name_match(struct d
 	to_match = data;
 	i_csdev = to_coresight_device(dev);
 
-	if (!strcmp(to_match, dev_name(&i_csdev->dev)))
+	if (to_match && !strcmp(to_match, dev_name(&i_csdev->dev)))
 		return 1;
 
 	return 0;


Patches currently in stable-queue which might be from mathieu.poirier@linaro.org are

queue-4.4/coresight-checking-for-null-string-in-coresight_name_match.patch