From 8335b312c7cc3653a6808e3041d76a50b3935a01 Mon Sep 17 00:00:00 2001 From: Sudip Mukherjee Date: Tue, 20 Dec 2016 21:09:04 +0000 Subject: [PATCH] nfc: fdp: fix NULL pointer dereference 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 Signed-off-by: Samuel Ortiz Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman --- drivers/nfc/fdp/i2c.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/nfc/fdp/i2c.c b/drivers/nfc/fdp/i2c.c index 532db28145c7..a5d7332dfce5 100644 --- a/drivers/nfc/fdp/i2c.c +++ b/drivers/nfc/fdp/i2c.c @@ -210,14 +210,14 @@ static irqreturn_t fdp_nci_i2c_irq_thread_fn(int irq, void *phy_id) 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)