Return value of a function 'kmalloc_array' is dereferenced at lag_conf.c:347
without checking for null, but it is usually checked for this function.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Denis Arefev <[email protected]>
---
drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
index 63907aeb3884..95ba6e92197d 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
@@ -276,7 +276,7 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
mutex_lock(&lag->lock);
list_for_each_entry_safe(entry, storage, &lag->group_list, list) {
- struct net_device *iter_netdev, **acti_netdevs;
+ struct net_device *iter_netdev, **acti_netdevs = NULL;
struct nfp_flower_repr_priv *repr_priv;
int active_count = 0, slaves = 0;
struct nfp_repr *repr;
@@ -308,6 +308,8 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
acti_netdevs = kmalloc_array(entry->slave_cnt,
sizeof(*acti_netdevs), GFP_KERNEL);
+ if (!acti_netdevs)
+ break;
/* Include sanity check in the loop. It may be that a bond has
* changed between processing the last notification and the
--
2.25.1
On Tue, Nov 15, 2022 at 11:56:37AM +0300, Denis Arefev wrote:
> [You don't often get email from [email protected]. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> Return value of a function 'kmalloc_array' is dereferenced at lag_conf.c:347
> without checking for null, but it is usually checked for this function.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Signed-off-by: Denis Arefev <[email protected]>
Hi Denis,
thanks for highlighting this problem.
> ---
> drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> index 63907aeb3884..95ba6e92197d 100644
> --- a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> +++ b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> @@ -276,7 +276,7 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
>
> mutex_lock(&lag->lock);
> list_for_each_entry_safe(entry, storage, &lag->group_list, list) {
> - struct net_device *iter_netdev, **acti_netdevs;
> + struct net_device *iter_netdev, **acti_netdevs = NULL;
I don't think it's necessary to set acti_netdevs here as
it is always set before use by the call to kmalloc_array().
> struct nfp_flower_repr_priv *repr_priv;
> int active_count = 0, slaves = 0;
> struct nfp_repr *repr;
> @@ -308,6 +308,8 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
>
> acti_netdevs = kmalloc_array(entry->slave_cnt,
> sizeof(*acti_netdevs), GFP_KERNEL);
> + if (!acti_netdevs)
> + break;
The indentation here doesn't look right.
Regarding the problem at hand, yes, I agree that it seems
that kmalloc_array() should be checked. But I am concerned that
simply break'ing here may lead to a bad state. And I'd like to ask
for some time to examine this more closely.
> /* Include sanity check in the loop. It may be that a bond has
> * changed between processing the last notification and the
> --
> 2.25.1
>
On Tue, 15 Nov 2022 11:56:37 +0300, Denis Arefev wrote:
> <...>
> @@ -308,6 +308,8 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
>
> acti_netdevs = kmalloc_array(entry->slave_cnt,
> sizeof(*acti_netdevs), GFP_KERNEL);
> + if (!acti_netdevs)
> + break;
I think we need give other entries and this entry itself one more chance by:
```
if (!acti_netdevs) {
schedule_delayed_work(&lag->work, NFP_FL_LAG_DELAY);
continue:
}
```
>
> /* Include sanity check in the loop. It may be that a bond has
> * changed between processing the last notification and the