[PATCH] gnss: fix potential error pointer dereference

[PATCH] gnss: fix potential error pointer dereference

[Dan Carpenter]

The gnss_allocate_device() function returns a mix of NULL and error
pointers on error.  It should only return one or the other.  Since the
callers both check for NULL, I've modified it to return NULL on error.

Fixes: 10f146639fee ("gnss: add receiver type support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/gnss/core.c b/drivers/gnss/core.c
index f30ef8338b3a..4291a0dd22aa 100644
--- a/drivers/gnss/core.c
+++ b/drivers/gnss/core.c
@@ -235,7 +235,7 @@ struct gnss_device *gnss_allocate_device(struct device *parent)
 	id = ida_simple_get(&gnss_minors, 0, GNSS_MINORS, GFP_KERNEL);
 	if (id < 0) {
 		kfree(gdev);
-		return ERR_PTR(id);
+		return NULL;
 	}
 
 	gdev->id = id;
@@ -270,7 +270,7 @@ struct gnss_device *gnss_allocate_device(struct device *parent)
 err_put_device:
 	put_device(dev);
 
-	return ERR_PTR(-ENOMEM);
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(gnss_allocate_device);
 

Re: [PATCH] gnss: fix potential error pointer dereference

[Johan Hovold]

On Tue, Jul 03, 2018 at 02:59:22PM +0300, Dan Carpenter wrote:
> The gnss_allocate_device() function returns a mix of NULL and error
> pointers on error.  It should only return one or the other.  Since the
> callers both check for NULL, I've modified it to return NULL on error.
> 
> Fixes: 10f146639fee ("gnss: add receiver type support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Ouch, thanks for catching this!

I think you got the wrong commit for the fixes tag above, however. That
should be:

Fixes: 2b6a44035143 ("gnss: add GNSS receiver subsystem")

Not sure if you want to send a v2, or if Greg can fix that when
applying. Apart from that:

Acked-by: Johan Hovold <johan@kernel.org>

Johan

Re: [PATCH] gnss: fix potential error pointer dereference

[Dan Carpenter]

On Tue, Jul 03, 2018 at 02:11:43PM +0200, Johan Hovold wrote:
> On Tue, Jul 03, 2018 at 02:59:22PM +0300, Dan Carpenter wrote:
> > The gnss_allocate_device() function returns a mix of NULL and error
> > pointers on error.  It should only return one or the other.  Since the
> > callers both check for NULL, I've modified it to return NULL on error.
> > 
> > Fixes: 10f146639fee ("gnss: add receiver type support")
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> Ouch, thanks for catching this!
> 
> I think you got the wrong commit for the fixes tag above, however. That
> should be:
> 
> Fixes: 2b6a44035143 ("gnss: add GNSS receiver subsystem")
> 

Oops.  That's what I intended, yes.  I will resend.

regards,
dan carpenter

[PATCH v2] gnss: fix potential error pointer dereference

[Dan Carpenter]

The gnss_allocate_device() function returns a mix of NULL and error
pointers on error.  It should only return one or the other.  Since the
callers both check for NULL, I've modified it to return NULL on error.

Fixes: 2b6a44035143 ("gnss: add GNSS receiver subsystem")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Johan Hovold <johan@kernel.org>
---
v2: Use the correct Fixes tag.

diff --git a/drivers/gnss/core.c b/drivers/gnss/core.c
index f30ef8338b3a..4291a0dd22aa 100644
--- a/drivers/gnss/core.c
+++ b/drivers/gnss/core.c
@@ -235,7 +235,7 @@ struct gnss_device *gnss_allocate_device(struct device *parent)
 	id = ida_simple_get(&gnss_minors, 0, GNSS_MINORS, GFP_KERNEL);
 	if (id < 0) {
 		kfree(gdev);
-		return ERR_PTR(id);
+		return NULL;
 	}
 
 	gdev->id = id;
@@ -270,7 +270,7 @@ struct gnss_device *gnss_allocate_device(struct device *parent)
 err_put_device:
 	put_device(dev);
 
-	return ERR_PTR(-ENOMEM);
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(gnss_allocate_device);