diff options
| author | WANG Cong <xiyou.wangcong@gmail.com> | 2016-07-05 22:12:36 -0700 |
|---|---|---|
| committer | Gerrit - the friendly Code Review server <code-review@localhost> | 2017-02-19 15:57:19 -0800 |
| commit | a1e9116dac9622bb803fc2c040e73db7655dc5f4 (patch) | |
| tree | 2091cf73330d647d2d174695df96318e6ae63c37 /drivers/net | |
| parent | 6f0b536eb7c5a7c7e8ae42418ec8e234a61920f1 (diff) | |
ppp: defer netns reference release for ppp channel
Matt reported that we have a NULL pointer dereference
in ppp_pernet() from ppp_connect_channel(),
i.e. pch->chan_net is NULL.
This is due to that a parallel ppp_unregister_channel()
could happen while we are in ppp_connect_channel(), during
which pch->chan_net set to NULL. Since we need a reference
to net per channel, it makes sense to sync the refcnt
with the life time of the channel, therefore we should
release this reference when we destroy it.
Fixes: 1f461dcdd296 ("ppp: take reference on channels netns")
Reported-by: Matt Bennett <Matt.Bennett@alliedtelesis.co.nz>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linux-ppp@vger.kernel.org
Cc: Guillaume Nault <g.nault@alphalink.fr>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-repo:https://source.codeaurora.org/quic/la/kernel/msm-4.4
Git-commit: 205e1e255c479f3fd77446415706463b282f94e4
Change-Id: Ic7ce3be365ebdc1505ed8ce68df981c855638a3c
Signed-off-by: Srinivasa Rao Kuppala <srkupp@codeaurora.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ppp/ppp_generic.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index fa76ca128e1b..e5bb870b5461 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -2390,8 +2390,6 @@ ppp_unregister_channel(struct ppp_channel *chan) spin_lock_bh(&pn->all_channels_lock); list_del(&pch->list); spin_unlock_bh(&pn->all_channels_lock); - put_net(pch->chan_net); - pch->chan_net = NULL; pch->file.dead = 1; wake_up_interruptible(&pch->file.rwait); |