| Message ID | 1618014803-17231-1-git-send-email-wangyingjie55@126.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1] libnvdimm, dax: Fix a missing check in nd_dax_probe() | expand |
On Fri, Apr 9, 2021 at 5:33 PM <wangyingjie55@126.com> wrote: > > From: Yingjie Wang <wangyingjie55@126.com> > > In nd_dax_probe(), nd_dax_alloc() may fail and return NULL. > Check for NULL before attempting to > use nd_dax to avoid a NULL pointer dereference. > > Fixes: c5ed9268643c ("libnvdimm, dax: autodetect support") > Signed-off-by: Yingjie Wang <wangyingjie55@126.com> > --- > drivers/nvdimm/dax_devs.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/nvdimm/dax_devs.c b/drivers/nvdimm/dax_devs.c > index 99965077bac4..b1426ac03f01 100644 > --- a/drivers/nvdimm/dax_devs.c > +++ b/drivers/nvdimm/dax_devs.c > @@ -106,6 +106,8 @@ int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns) > > nvdimm_bus_lock(&ndns->dev); hmmm... > nd_dax = nd_dax_alloc(nd_region); > + if (!nd_dax) > + return -ENOMEM; Can you spot the bug this introduces? See the hint above. > nd_pfn = &nd_dax->nd_pfn; > dax_dev = nd_pfn_devinit(nd_pfn, ndns); > nvdimm_bus_unlock(&ndns->dev); > -- > 2.7.4 >
diff --git a/drivers/nvdimm/dax_devs.c b/drivers/nvdimm/dax_devs.c index 99965077bac4..b1426ac03f01 100644 --- a/drivers/nvdimm/dax_devs.c +++ b/drivers/nvdimm/dax_devs.c @@ -106,6 +106,8 @@ int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns) nvdimm_bus_lock(&ndns->dev); nd_dax = nd_dax_alloc(nd_region); + if (!nd_dax) + return -ENOMEM; nd_pfn = &nd_dax->nd_pfn; dax_dev = nd_pfn_devinit(nd_pfn, ndns); nvdimm_bus_unlock(&ndns->dev);