| Message ID | 20221115085637.72193-1-arefev@swemel.ru (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | lag_conf: Added pointer check | expand |
On Tue, Nov 15, 2022 at 11:56:37AM +0300, Denis Arefev wrote: > [You don't often get email from arefev@swemel.ru. 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 <arefev@swemel.ru> 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
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
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 <arefev@swemel.ru> --- drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)