From: Roman Mashak <mrv@xxxxxxxxxxxx>
This patch has been added to the stable tree. If you have any
objections, please let us know.
===============
[ Upstream commit edb9d1bff4bbe19b8ae0e71b1f38732591a9eeb2 ]
When tc actions are loaded as a module and no actions have been installed,
flushing them would result in actions removed from the memory, but modules
reference count not being decremented, so that the modules would not be
unloaded.
Following is example with GACT action:
% sudo modprobe act_gact
% lsmod
Module Size Used by
act_gact 16384 0
%
% sudo tc actions ls action gact
%
% sudo tc actions flush action gact
% lsmod
Module Size Used by
act_gact 16384 1
% sudo tc actions flush action gact
% lsmod
Module Size Used by
act_gact 16384 2
% sudo rmmod act_gact
rmmod: ERROR: Module act_gact is in use
....
After the fix:
% lsmod
Module Size Used by
act_gact 16384 0
%
% sudo tc actions add action pass index 1
% sudo tc actions add action pass index 2
% sudo tc actions add action pass index 3
% lsmod
Module Size Used by
act_gact 16384 3
%
% sudo tc actions flush action gact
% lsmod
Module Size Used by
act_gact 16384 0
%
% sudo tc actions flush action gact
% lsmod
Module Size Used by
act_gact 16384 0
% sudo rmmod act_gact
% lsmod
Module Size Used by
%
Fixes: f97017cdefef ("net-sched: Fix actions flushing")
Signed-off-by: Roman Mashak <mrv@xxxxxxxxxxxx>
Signed-off-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Acked-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
net/sched/act_api.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index f8d9c2a2c451..c9387f62f634 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -802,10 +802,8 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
goto out_module_put;
err = a.ops->walk(skb, &dcb, RTM_DELACTION, &a);
- if (err < 0)
+ if (err <= 0)
goto out_module_put;
- if (err == 0)
- goto noflush_out;
nla_nest_end(skb, nest);
@@ -822,7 +820,6 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
out_module_put:
module_put(a.ops->owner);
err_out:
-noflush_out:
kfree_skb(skb);
return err;
}
--
2.11.0