| Message ID | 4922b1c14d384a1d9fa88c857f79a50ab1e4053d.1521417146.git.dcaratti@redhat.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | fix idr leak in actions | expand |
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c index c2914e9a4a6f..c49cb61adedf 100644 --- a/net/sched/act_vlan.c +++ b/net/sched/act_vlan.c @@ -195,7 +195,7 @@ static int tcf_vlan_init(struct net *net, struct nlattr *nla, ASSERT_RTNL(); p = kzalloc(sizeof(*p), GFP_KERNEL); if (!p) { - if (ovr) + if (ret == ACT_P_CREATED) tcf_idr_release(*a, bind); return -ENOMEM; }
tcf_vlan_init() can fail after the idr has been successfully reserved. When this happens, every subsequent attempt to configure vlan rules using the same idr value will systematically fail with -ENOSPC, unless the first attempt was done using the 'replace' keyword. # tc action add action vlan pop index 100 RTNETLINK answers: Cannot allocate memory We have an error talking to the kernel # tc action add action vlan pop index 100 RTNETLINK answers: No space left on device We have an error talking to the kernel # tc action add action vlan pop index 100 RTNETLINK answers: No space left on device We have an error talking to the kernel ... Fix this in tcf_vlan_init(), ensuring that tcf_idr_release() is called on the error path when the idr has been reserved, but not yet inserted. Also, don't test 'ovr' in the error path, to avoid a 'replace' failure implicitly become a 'delete' that leaks refcount in act_vlan module: # rmmod act_vlan; modprobe act_vlan # tc action add action vlan push id 5 index 100 # tc action replace action vlan push id 7 index 100 RTNETLINK answers: Cannot allocate memory We have an error talking to the kernel # tc action list action vlan # # rmmod act_vlan # rmmod: ERROR: Module act_vlan is in use Fixes: 4c5b9d9642c8 ("act_vlan: VLAN action rewrite to use RCU lock/unlock and update") Fixes: 65a206c01e8e ("net/sched: Change act_api and act_xxx modules to use IDR") Signed-off-by: Davide Caratti <dcaratti@redhat.com> --- net/sched/act_vlan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)