| Message ID | 1648110940-4684-1-git-send-email-unSimple1993@163.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | [v1] soc: bcm: Check for NULL return of devm_kzalloc() | expand |
+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@163.com> 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;
Hello! s/return/result/ in the subject. On 3/24/22 11:35 AM, QintaoShen wrote: > As the potential failuer of allocation, devm_kzalloc() may return NULL. > Then the 'pd->pmb' and the follow lines of code may bring null pointer dereference. Following. > Therefore, it is better to check the return value of devm_kzalloc() to avoid this confusion. > > Signed-off-by: QintaoShen <unSimple1993@163.com> > --- > 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); Please keep an empty line after declaration. > + if (!pd) > + return -ENOMEM; > > pd->pmb = pmb; > pd->data = e; MBR, Sergey
OK. Here is the new version.
Signed-off-by: QintaoShen <unSimple1993@163.com>
---
drivers/soc/bcm/bcm63xx/bcm-pmb.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/soc/bcm/bcm63xx/bcm-pmb.c
b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
index 7bbe46e..cc20ffb 100644
--- a/drivers/soc/bcm/bcm63xx/bcm-pmb.c
+++ b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
@@ -312,6 +312,9 @@ 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;
+
pd->pmb = pmb;
pd->data = e;
pd->genpd.name = e->name;
On 3/24/2022 1:35 AM, QintaoShen wrote: > As the potential failuer of allocation, devm_kzalloc() may return NULL. > 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@163.com> Applied to https://github.com/Broadcom/stblinux/commits/drivers/next, thanks! I modified your patch to have a Fixes: tag as replied, and follow Sergey's style recommendation.
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; pd->pmb = pmb; pd->data = e;
As the potential failuer of allocation, devm_kzalloc() may return NULL. 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@163.com> --- drivers/soc/bcm/bcm63xx/bcm-pmb.c | 2 ++ 1 file changed, 2 insertions(+)