diff options
| author | Davide Caratti <dcaratti@redhat.com> | 2018-03-19 15:31:27 +0100 | 
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-03-21 18:12:27 -0400 | 
| commit | d7f20015736048f494988093b59fe513dc232ce9 (patch) | |
| tree | 0d896a8d0fef849b6e1ce071ad81a99bb24cc8e0 | |
| parent | 1e46ef1762bb2e52f0f996131a4d16ed4e9fd065 (diff) | |
net/sched: fix idr leak in the error path of tcf_vlan_init()
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")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sched/act_vlan.c | 2 | 
1 files changed, 1 insertions, 1 deletions
| 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;  	} | 
