Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 21:21:41 +00:00
Code Issues Packages Projects Releases Wiki Activity

net sched actions: decrement module reference count after table flush.

Browse Source 
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: f97017cdef ("net-sched: Fix actions flushing")
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Roman Mashak 2017-02-24 11:00:32 -05:00 committed by David S. Miller
parent 9d25af69b3
commit edb9d1bff4
1 changed files with 1 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
net/sched/act_api.c
View File

@ -859,10 +859,8 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
goto out_module_put;
err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
if (err < 0)
if (err <= 0)
goto out_module_put;
if (err == 0)
goto noflush_out;
nla_nest_end(skb, nest);
@ -879,7 +877,6 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
out_module_put:
module_put(ops->owner);
err_out:
noflush_out:
kfree_skb(skb);
return err;
}