2023-04-07 01:32:49

by Chen Aotian

Subject: [PATCH] ieee802154: hwsim: Fix possible memory leaks

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

Signed-off-by: Chen Aotian <[email protected]>
---
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;
}
--
2.25.1

2023-04-07 08:02:34

by Miquel Raynal

Subject: Re: [PATCH] ieee802154: hwsim: Fix possible memory leaks

Hi Chen,

[email protected] wrote on Fri, 7 Apr 2023 09:26:26 +0800:

> After replacing e->info, it is necessary to free the old einfo.
>
> Signed-off-by: Chen Aotian <[email protected]>
> ---
> 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;
> }

I'm not an RCU expert but the fix LGTM.

Reviewed-by: Miquel Raynal <[email protected]>

What about adding:

Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
Cc: [email protected]

Thanks,
Miquèl

2023-04-07 09:59:39

by Chen Aotian

Subject: Re: [PATCH] ieee802154: hwsim: Fix possible memory leaks

> [email protected] wrote on Date: Fri, 7 Apr 2023 10:01:48 +0200:
> > [email protected] wrote on Fri, 7 Apr 2023 09:26:26 +0800:

> > After replacing e->info, it is necessary to free the old einfo.
> >
> > Signed-off-by: Chen Aotian <[email protected]>
> > ---
> > 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;
> > }
>
> I'm not an RCU expert but the fix LGTM.

> What about adding:

> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
> Cc: [email protected]

Sure, I will resend this patch soon with adding those

Thanks,
Chen