Re: [PATCH v1] soc: bcm: Check for NULL return of devm_kzalloc()

From: Florian Fainelli
Date: Thu Mar 24 2022 - 13:04:51 EST


+Rafal,

On 3/24/22 01:35, QintaoShen wrote:
As the potential failuer of allocation, devm_kzalloc() may return NULL.

s/failuer/failure/

Then the 'pd->pmb' and the follow lines of code may bring null pointer dereference.

Therefore, it is better to check the return value of devm_kzalloc() to avoid this confusion.

Signed-off-by: QintaoShen <unSimple1993@xxxxxxx>

Fixes: 8bcac4011ebe ("soc: bcm: add PM driver for Broadcom's PMB")

---
drivers/soc/bcm/bcm63xx/bcm-pmb.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/soc/bcm/bcm63xx/bcm-pmb.c b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
index 7bbe46e..55bf389 100644
--- a/drivers/soc/bcm/bcm63xx/bcm-pmb.c
+++ b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
@@ -311,6 +311,8 @@ static int bcm_pmb_probe(struct platform_device *pdev)
for (e = table; e->name; e++) {
struct bcm_pmb_pm_domain *pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;

I am of two minds as to what the appropriate behavior could be here, we could equally use an:

if (!pd)
continue;

or do what you are doing.

pd->pmb = pmb;
pd->data = e;


--
Florian