[PATCH] ieee802154: hwsim: Fix possible memory leak in hwsim_subscribe_all_others

[PATCH] ieee802154: hwsim: Fix possible memory leak in hwsim_subscribe_all_others

[Dongliang Mu]

In hwsim_subscribe_all_others, the error handling code performs
incorrectly if the second hwsim_alloc_edge fails. When this issue occurs,
it goes to sub_fail, without cleaning the edges allocated before.

Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
---
 drivers/net/ieee802154/mac802154_hwsim.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
index da9135231c07..366eaae3550a 100644
--- a/drivers/net/ieee802154/mac802154_hwsim.c
+++ b/drivers/net/ieee802154/mac802154_hwsim.c
@@ -715,6 +715,8 @@ static int hwsim_subscribe_all_others(struct hwsim_phy *phy)
 
 	return 0;
 
+sub_fail:
+	hwsim_edge_unsubscribe_me(phy);
 me_fail:
 	rcu_read_lock();
 	list_for_each_entry_rcu(e, &phy->edges, list) {
@@ -722,8 +724,6 @@ static int hwsim_subscribe_all_others(struct hwsim_phy *phy)
 		hwsim_free_edge(e);
 	}
 	rcu_read_unlock();
-sub_fail:
-	hwsim_edge_unsubscribe_me(phy);
 	return -ENOMEM;
 }
 
-- 
2.25.1

Re: [PATCH] ieee802154: hwsim: Fix possible memory leak in hwsim_subscribe_all_others

[Alexander Aring]

Hi,

On Thu, 10 Jun 2021 at 21:58, Dongliang Mu <mudongliangabcd@gmail.com> wrote:
>
> In hwsim_subscribe_all_others, the error handling code performs
> incorrectly if the second hwsim_alloc_edge fails. When this issue occurs,
> it goes to sub_fail, without cleaning the edges allocated before.
>
> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
>  drivers/net/ieee802154/mac802154_hwsim.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ieee802154/mac802154_hwsim.c b/drivers/net/ieee802154/mac802154_hwsim.c
> index da9135231c07..366eaae3550a 100644
> --- a/drivers/net/ieee802154/mac802154_hwsim.c
> +++ b/drivers/net/ieee802154/mac802154_hwsim.c
> @@ -715,6 +715,8 @@ static int hwsim_subscribe_all_others(struct hwsim_phy *phy)
>
>         return 0;
>
> +sub_fail:
> +       hwsim_edge_unsubscribe_me(phy);
>  me_fail:
>         rcu_read_lock();
>         list_for_each_entry_rcu(e, &phy->edges, list) {
> @@ -722,8 +724,6 @@ static int hwsim_subscribe_all_others(struct hwsim_phy *phy)
>                 hwsim_free_edge(e);
>         }
>         rcu_read_unlock();
> -sub_fail:

this goto needs to be removed and all goto cases need to end in
me_fail (better named to be fail only).
In an error case both loops need to be iterated again to cleanup.

- Alex

Re: [PATCH] ieee802154: hwsim: Fix possible memory leak in hwsim_subscribe_all_others

[Alexander Aring]

Hi,

On Thu, 10 Jun 2021 at 21:58, Dongliang Mu <mudongliangabcd@gmail.com> wrote:
>
> In hwsim_subscribe_all_others, the error handling code performs
> incorrectly if the second hwsim_alloc_edge fails. When this issue occurs,
> it goes to sub_fail, without cleaning the edges allocated before.
>
> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>

Acked-by: Alexander Aring <aahringo@redhat.com>

sorry, it is a correct fix. Thanks.

- Alex

Re: [PATCH] ieee802154: hwsim: Fix possible memory leak in hwsim_subscribe_all_others

[Stefan Schmidt]

Hello.

On 12.06.21 14:49, Alexander Aring wrote:
> Hi,
> 
> On Thu, 10 Jun 2021 at 21:58, Dongliang Mu <mudongliangabcd@gmail.com> wrote:
>>
>> In hwsim_subscribe_all_others, the error handling code performs
>> incorrectly if the second hwsim_alloc_edge fails. When this issue occurs,
>> it goes to sub_fail, without cleaning the edges allocated before.
>>
>> Fixes: f25da51fdc38 ("ieee802154: hwsim: add replacement for fakelb")
>> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> 
> Acked-by: Alexander Aring <aahringo@redhat.com>
> 
> sorry, it is a correct fix. Thanks.


This patch has been applied to the wpan tree and will be
part of the next pull request to net. Thanks!

regards
Stefan Schmidt