[-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain; charset=y, Size: 942 bytes --] From: Yingjie Wang <wangyingjie55@126.com> In nd_dax_probe(), 'nd_dax' is allocated by nd_dax_alloc(). nd_dax_alloc() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. 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); 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); -- 2.7.4 [-- Attachment #2: Type: text/plain, Size: 167 bytes --] _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
From: Yingjie Wang <wangyingjie55@126.com> In nd_dax_probe(), 'nd_dax' is allocated by nd_dax_alloc(). nd_dax_alloc() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. 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); 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); -- 2.7.4 _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
From: Yingjie Wang <wangyingjie55@126.com> In nd_dax_probe(), 'nd_dax' is allocated by nd_dax_alloc(). nd_dax_alloc() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. 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); 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); -- 2.7.4 _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
On Thu, Apr 08, 2021 at 06:58:26PM -0700, wangyingjie55@126.com wrote: > From: Yingjie Wang <wangyingjie55@126.com> > > In nd_dax_probe(), 'nd_dax' is allocated by nd_dax_alloc(). > nd_dax_alloc() may fail and return NULL, so we should better check Avoid the use of 'we'. > it's return value to avoid a NULL pointer dereference > a bit later in the code. How about: "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> The code looks good though. Ira > --- > 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); > 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); > -- > 2.7.4 > _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
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); 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); -- 2.7.4 _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
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 > _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org