Patch "nfc: fdp: fix NULL pointer dereference" has been added to the 4.4-stable tree

Patch "nfc: fdp: fix NULL pointer dereference" 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

    nfc: fdp: fix NULL pointer dereference

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:
     nfc-fdp-fix-null-pointer-dereference.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 b6355fb3f5f40bbce165847d277e64896cab8f95 Mon Sep 17 00:00:00 2001
From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Date: Tue, 20 Dec 2016 21:09:04 +0000
Subject: nfc: fdp: fix NULL pointer dereference

From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>

commit b6355fb3f5f40bbce165847d277e64896cab8f95 upstream.

We are checking phy after dereferencing it. We can print the debug
information after checking it. If phy is NULL then we will get a good
stack trace to tell us that we are in this irq handler.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/nfc/fdp/i2c.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/nfc/fdp/i2c.c
+++ b/drivers/nfc/fdp/i2c.c
@@ -210,14 +210,14 @@ static irqreturn_t fdp_nci_i2c_irq_threa
 	struct sk_buff *skb;
 	int r;
 
-	client = phy->i2c_dev;
-	dev_dbg(&client->dev, "%s\n", __func__);
-
 	if (!phy || irq != phy->i2c_dev->irq) {
 		WARN_ON_ONCE(1);
 		return IRQ_NONE;
 	}
 
+	client = phy->i2c_dev;
+	dev_dbg(&client->dev, "%s\n", __func__);
+
 	r = fdp_nci_i2c_read(phy, &skb);
 
 	if (r == -EREMOTEIO)


Patches currently in stable-queue which might be from sudipm.mukherjee@gmail.com are

queue-4.4/nfc-fdp-fix-null-pointer-dereference.patch