From: Pan Bian <bianpan2016@163.com>
Date: Sun, 23 Apr 2017 09:52:55 +0000 (+0800)
Subject: staging: comedi: addi_apci_3xxx: check return value
X-Git-Tag: Ubuntu-5.13.0-19.19~13541^2~100
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=a455178e59f2b3591840cc543cf637424bd572d7;p=mirror_ubuntu-jammy-kernel.git

staging: comedi: addi_apci_3xxx: check return value

Function pci_ioremap_bar() will return a NULL pointer if there is no
enough memory. However, in function apci3xxx_auto_attach(), the return
value of function pci_ioremap_bar() is not validated. This may result in
NULL dereference in following access to dev->mmio. This patch fixes the
bug.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/comedi/drivers/addi_apci_3xxx.c b/drivers/staging/comedi/drivers/addi_apci_3xxx.c
index 82c22110f128..be1f6133ff1c 100644
--- a/drivers/staging/comedi/drivers/addi_apci_3xxx.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3xxx.c
@@ -787,6 +787,8 @@ static int apci3xxx_auto_attach(struct comedi_device *dev,
 
 	dev->iobase = pci_resource_start(pcidev, 2);
 	dev->mmio = pci_ioremap_bar(pcidev, 3);
+	if (!dev->mmio)
+		return -ENOMEM;
 
 	if (pcidev->irq > 0) {
 		ret = request_irq(pcidev->irq, apci3xxx_irq_handler,