[PATCH v1 1/1] net/9p/usbg: fix handling of the failed kzalloc() memory allocation

[PATCH v1 1/1] net/9p/usbg: fix handling of the failed kzalloc() memory allocation

[Mirsad Todorovac]

On the linux-next, next-20241108 vanilla kernel, the coccinelle tool gave the
following error report:

./net/9p/trans_usbg.c:912:5-11: ERROR: allocation function on line 911 returns
NULL not ERR_PTR on failure

kzalloc() failure is fixed to handle the NULL return case on the memory exhaustion.

Fixes: a3be076dc174d ("net/9p/usbg: Add new usb gadget function transport")
Cc: Michael Grzeschik <m.grzeschik@pengutronix.de>
Cc: Eric Van Hensbergen <ericvh@kernel.org>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Christian Schoenebeck <linux_oss@crudebyte.com>
Cc: v9fs@lists.linux.dev
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Mirsad Todorovac <mtodorovac69@gmail.com>
---
 v1:
    initial version.

 net/9p/trans_usbg.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/9p/trans_usbg.c b/net/9p/trans_usbg.c
index 975b76839dca..6b694f117aef 100644
--- a/net/9p/trans_usbg.c
+++ b/net/9p/trans_usbg.c
@@ -909,9 +909,9 @@ static struct usb_function_instance *usb9pfs_alloc_instance(void)
 	usb9pfs_opts->buflen = DEFAULT_BUFLEN;
 
 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (IS_ERR(dev)) {
+	if (!dev) {
 		kfree(usb9pfs_opts);
-		return ERR_CAST(dev);
+		return ERR_PTR(-ENOMEM);
 	}
 
 	usb9pfs_opts->dev = dev;
-- 
2.43.0

Re: [PATCH v1 1/1] net/9p/usbg: fix handling of the failed kzalloc() memory allocation

[Dominique Martinet]

Mirsad Todorovac wrote on Sat, Nov 09, 2024 at 10:18:41PM +0100:
> On the linux-next, next-20241108 vanilla kernel, the coccinelle tool gave the
> following error report:
> 
> ./net/9p/trans_usbg.c:912:5-11: ERROR: allocation function on line 911 returns
> NULL not ERR_PTR on failure
> 
> kzalloc() failure is fixed to handle the NULL return case on the memory exhaustion.

Thank you, I've taken this in 9p-next and will submit it to Linus next
cycle

-- 
Dominique

Re: [PATCH v1 1/1] net/9p/usbg: fix handling of the failed kzalloc() memory allocation

[Mirsad Todorovac]

Hi,

On 11/16/24 09:25, Dominique Martinet wrote:
> Mirsad Todorovac wrote on Sat, Nov 09, 2024 at 10:18:41PM +0100:
>> On the linux-next, next-20241108 vanilla kernel, the coccinelle tool gave the
>> following error report:
>>
>> ./net/9p/trans_usbg.c:912:5-11: ERROR: allocation function on line 911 returns
>> NULL not ERR_PTR on failure
>>
>> kzalloc() failure is fixed to handle the NULL return case on the memory exhaustion.
> 
> Thank you, I've taken this in 9p-next and will submit it to Linus next
> cycle

Hi, Dominique,

Sorry for the late reply, but yes, it is perfectly OK for the patch to go with the
next cycle.

I confirm I can see the commit in the torvalds tree, so this is a minor patch (+2/-2 lines),
but a proof of concept that it can be done.

Best regards,
Mirsad Todorovac