[net,v3] nfp: flower: Added pointer check and continue
Commit Message
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.
Fixes: bb9a8d031140 ("nfp: flower: monitor and offload LAG groups")
Signed-off-by: Denis Arefev <arefev@swemel.ru>
---
drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
Comments
On Fri, Nov 18, 2022 at 11:03:17AM +0300, Denis Arefev wrote:
> 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.
> Fixes: bb9a8d031140 ("nfp: flower: monitor and offload LAG groups")
> Signed-off-by: Denis Arefev <arefev@swemel.ru>
> ---
> drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 6 +++++-
> 1 file changed, 5 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..1aaec4cb9f55 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;
Small nit, otherwise looks fine.
I think there is no need to set it to NULL here as it is always set to
return value from kmalloc_array().
Thanks
> struct nfp_flower_repr_priv *repr_priv;
> int active_count = 0, slaves = 0;
> struct nfp_repr *repr;
> @@ -308,6 +308,10 @@ 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) {
> + 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
> --
> 2.25.1
>
On Fri, Nov 18, 2022 at 11:03:17AM +0300, Denis Arefev wrote:
> 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.
> Fixes: bb9a8d031140 ("nfp: flower: monitor and offload LAG groups")
> Signed-off-by: Denis Arefev <arefev@swemel.ru>
> ---
> drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
<...>
> acti_netdevs = kmalloc_array(entry->slave_cnt,
> sizeof(*acti_netdevs), GFP_KERNEL);
> + if (!acti_netdevs) {
> + schedule_delayed_work(&lag->work, NFP_FL_LAG_DELAY);
> + continue;
It is usually not good idea to continue after memory allocation fails.
So or add __GFP_NOWARN with a comment why it is safe to continue or bail
out from this loop.
Thanks
> + }
>
> /* Include sanity check in the loop. It may be that a bond has
> * changed between processing the last notification and the
> --
> 2.25.1
>
@@ -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 +308,10 @@ 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) {
+ 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