diff mbox series

ieee802154: hwsim: Fix possible memory leaks

Message ID 20230407095301.45858-1-chenaotian2@163.com (mailing list archive)
State Superseded
Headers show
Series ieee802154: hwsim: Fix possible memory leaks | expand

Commit Message

Chen Aotian April 7, 2023, 9:53 a.m. UTC
After replacing e->info, it is necessary to free the old einfo.

Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
Signed-off-by: Chen Aotian <chenaotian2@163.com>
---
 drivers/net/ieee802154/mac802154_hwsim.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Miquel Raynal April 7, 2023, 1:46 p.m. UTC | #1
Hi Chen,

(resending my answer since apparently the first time it failed)

chenaotian2@163.com wrote on Fri,  7 Apr 2023 17:53:01 +0800:

> After replacing e->info, it is necessary to free the old einfo.

The title should contain:
- wpan (that's the tree you target, use --subject-prefix="PATCH wpan"
  of git-format-patch)
- v2 (because that's a new version, use the -v2 option of
  git-format-patch)

Apparently I mis-wrote the stable address, just add this line to the
commit:

Cc: stable@vger.kernel.org

(right now you sent it to stable@vger.kernelorg which is incorrect,
sorry for the typo)
 
> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")

And please carry the tags:

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

> Signed-off-by: Chen Aotian <chenaotian2@163.com>
> ---
>  drivers/net/ieee802154/mac802154_hwsim.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
> index 8445c2189..6e7e10b17 100644
> --- a/drivers/net/ieee802154/mac802154_hwsim.c
> +++ b/drivers/net/ieee802154/mac802154_hwsim.c
> @@ -685,7 +685,7 @@ static int hwsim_del_edge_nl(struct sk_buff *msg, struct genl_info *info)
>  static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
>  {
>  	struct nlattr *edge_attrs[MAC802154_HWSIM_EDGE_ATTR_MAX + 1];
> -	struct hwsim_edge_info *einfo;
> +	struct hwsim_edge_info *einfo, *einfo_old;
>  	struct hwsim_phy *phy_v0;
>  	struct hwsim_edge *e;
>  	u32 v0, v1;
> @@ -723,8 +723,10 @@ static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
>  	list_for_each_entry_rcu(e, &phy_v0->edges, list) {
>  		if (e->endpoint->idx == v1) {
>  			einfo->lqi = lqi;
> +			einfo_old = rcu_dereference(e->info);
>  			rcu_assign_pointer(e->info, einfo);
>  			rcu_read_unlock();
> +			kfree_rcu(einfo_old, rcu);
>  			mutex_unlock(&hwsim_phys_lock);
>  			return 0;
>  		}


Thanks,
Miquèl
Alexander Aring April 7, 2023, 10:20 p.m. UTC | #2
Hi,

On Fri, Apr 7, 2023 at 5:55 AM Chen Aotian <chenaotian2@163.com> wrote:
>
> After replacing e->info, it is necessary to free the old einfo.
>
> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
> Signed-off-by: Chen Aotian <chenaotian2@163.com>
> ---
>  drivers/net/ieee802154/mac802154_hwsim.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
> index 8445c2189..6e7e10b17 100644
> --- a/drivers/net/ieee802154/mac802154_hwsim.c
> +++ b/drivers/net/ieee802154/mac802154_hwsim.c
> @@ -685,7 +685,7 @@ static int hwsim_del_edge_nl(struct sk_buff *msg, struct genl_info *info)
>  static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
>  {
>         struct nlattr *edge_attrs[MAC802154_HWSIM_EDGE_ATTR_MAX + 1];
> -       struct hwsim_edge_info *einfo;
> +       struct hwsim_edge_info *einfo, *einfo_old;
>         struct hwsim_phy *phy_v0;
>         struct hwsim_edge *e;
>         u32 v0, v1;
> @@ -723,8 +723,10 @@ static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
>         list_for_each_entry_rcu(e, &phy_v0->edges, list) {
>                 if (e->endpoint->idx == v1) {
>                         einfo->lqi = lqi;
> +                       einfo_old = rcu_dereference(e->info);
>                         rcu_assign_pointer(e->info, einfo);

nitpick rcu_replace_pointer() can be used here.*

- Alex
Chen Aotian April 8, 2023, 6:43 a.m. UTC | #3
Fri, 7 Apr 2023 18:20:32 -0400 Alexander Aring <aahringo@redhat.com> wrote:
>
> On Fri, Apr 7, 2023 at 5:55 AM Chen Aotian <chenaotian2@163.com> wrote:
> >
> > After replacing e->info, it is necessary to free the old einfo.
> >
> > Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
> > Signed-off-by: Chen Aotian <chenaotian2@163.com>
> > ---
> >  drivers/net/ieee802154/mac802154_hwsim.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
> > index 8445c2189..6e7e10b17 100644
> > --- a/drivers/net/ieee802154/mac802154_hwsim.c
> > +++ b/drivers/net/ieee802154/mac802154_hwsim.c
> > @@ -685,7 +685,7 @@ static int hwsim_del_edge_nl(struct sk_buff *msg, struct genl_info *info)
> >  static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
> >  {
> >         struct nlattr *edge_attrs[MAC802154_HWSIM_EDGE_ATTR_MAX + 1];
> > -       struct hwsim_edge_info *einfo;
> > +       struct hwsim_edge_info *einfo, *einfo_old;
> >         struct hwsim_phy *phy_v0;
> >         struct hwsim_edge *e;
> >         u32 v0, v1;
> > @@ -723,8 +723,10 @@ static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
> >         list_for_each_entry_rcu(e, &phy_v0->edges, list) {
> >                 if (e->endpoint->idx == v1) {
> >                         einfo->lqi = lqi;
> > +                       einfo_old = rcu_dereference(e->info);
> >                         rcu_assign_pointer(e->info, einfo);
> 
> nitpick rcu_replace_pointer() can be used here.*

Thank you for your suggestion, Alex. BTW, thanks for Miquèl's patient 
guidance too, I just started trying to submit patches to the kernel, 
I will do batter.

Thanks,
Chen
diff mbox series

Patch

diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
index 8445c2189..6e7e10b17 100644
--- a/drivers/net/ieee802154/mac802154_hwsim.c
+++ b/drivers/net/ieee802154/mac802154_hwsim.c
@@ -685,7 +685,7 @@  static int hwsim_del_edge_nl(struct sk_buff *msg, struct genl_info *info)
 static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
 {
 	struct nlattr *edge_attrs[MAC802154_HWSIM_EDGE_ATTR_MAX + 1];
-	struct hwsim_edge_info *einfo;
+	struct hwsim_edge_info *einfo, *einfo_old;
 	struct hwsim_phy *phy_v0;
 	struct hwsim_edge *e;
 	u32 v0, v1;
@@ -723,8 +723,10 @@  static int hwsim_set_edge_lqi(struct sk_buff *msg, struct genl_info *info)
 	list_for_each_entry_rcu(e, &phy_v0->edges, list) {
 		if (e->endpoint->idx == v1) {
 			einfo->lqi = lqi;
+			einfo_old = rcu_dereference(e->info);
 			rcu_assign_pointer(e->info, einfo);
 			rcu_read_unlock();
+			kfree_rcu(einfo_old, rcu);
 			mutex_unlock(&hwsim_phys_lock);
 			return 0;
 		}