2022-07-04 13:20:45

by Jianglei Nie

Subject: [PATCH] net: macsec: fix potential resource leak in macsec_add_rxsa() and macsec_add_txsa()

init_rx_sa() allocates relevant resource for rx_sa->stats and rx_sa->
key.tfm with alloc_percpu() and macsec_alloc_tfm(). When some error
occurs after init_rx_sa() is called in macsec_add_rxsa(), the function
released rx_sa with kfree() without releasing rx_sa->stats and rx_sa->
key.tfm, which will lead to a resource leak.

We should call macsec_rxsa_put() instead of kfree() to decrease the ref
count of rx_sa and release the relevant resource if the refcount is 0.
The same bug exists in macsec_add_txsa() for tx_sa as well. This patch
fixes the above two bugs.

Signed-off-by: Jianglei Nie <[email protected]>
---
drivers/net/macsec.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 817577e713d7..ac3ff624a8dd 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -1842,7 +1842,7 @@ static int macsec_add_rxsa(struct sk_buff *skb, struct genl_info *info)
return 0;

cleanup:
- kfree(rx_sa);
+ macsec_rxsa_put(rx_sa);
rtnl_unlock();
return err;
}
@@ -2085,7 +2085,7 @@ static int macsec_add_txsa(struct sk_buff *skb, struct genl_info *info)

cleanup:
secy->operational = was_operational;
- kfree(tx_sa);
+ macsec_txsa_put(tx_sa);
rtnl_unlock();
return err;
}
--
2.25.1

2022-07-05 14:37:52

by Paolo Abeni

Subject: Re: [PATCH] net: macsec: fix potential resource leak in macsec_add_rxsa() and macsec_add_txsa()

Hello,

On Mon, 2022-07-04 at 20:33 +0800, Jianglei Nie wrote:
> init_rx_sa() allocates relevant resource for rx_sa->stats and rx_sa->
> key.tfm with alloc_percpu() and macsec_alloc_tfm(). When some error
> occurs after init_rx_sa() is called in macsec_add_rxsa(), the function
> released rx_sa with kfree() without releasing rx_sa->stats and rx_sa->
> key.tfm, which will lead to a resource leak.
>
> We should call macsec_rxsa_put() instead of kfree() to decrease the ref
> count of rx_sa and release the relevant resource if the refcount is 0.
> The same bug exists in macsec_add_txsa() for tx_sa as well. This patch
> fixes the above two bugs.
>
> Signed-off-by: Jianglei Nie <[email protected]>

The patch LGTM. This looks like -net material, so please repost
specifying the correct tree into the patch subj and more importantnly
including a suitable 'Fixes' tag into the commit message.

Thanks!

Paolo