path: root/net/atm/pppoatm.c
diff options
authorKrzysztof Mazur <krzysiek@podlesie.net>2012-11-10 22:33:19 (GMT)
committerDavid Woodhouse <David.Woodhouse@intel.com>2012-11-30 12:21:42 (GMT)
commit071d93931a75dc1f82f0baa9959613af81c5a032 (patch)
treea6a4a61cacc37fe189aa7676871c654f37ef244f /net/atm/pppoatm.c
parent3ac108006fd7f20cb8fc8ea2287f1497bcda00a1 (diff)
pppoatm: drop frames to not-ready vcc
The vcc_destroy_socket() closes vcc before the protocol is detached from vcc by calling vcc->push() with NULL skb. This leaves some time window, where the protocol may call vcc->send() on closed vcc and crash. Now pppoatm_send(), like vcc_sendmsg(), checks for vcc flags that indicate that vcc is not ready. If the vcc is not ready we just drop frame. Queueing frames is much more complicated because we don't have callbacks that inform us about vcc flags changes. Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'net/atm/pppoatm.c')
1 files changed, 7 insertions, 0 deletions
diff --git a/net/atm/pppoatm.c b/net/atm/pppoatm.c
index c4a57bc..aeb726c 100644
--- a/net/atm/pppoatm.c
+++ b/net/atm/pppoatm.c
@@ -284,6 +284,13 @@ static int pppoatm_send(struct ppp_channel *chan, struct sk_buff *skb)
if (sock_owned_by_user(sk_atm(vcc)))
goto nospace;
+ if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
+ test_bit(ATM_VF_CLOSE, &vcc->flags) ||
+ !test_bit(ATM_VF_READY, &vcc->flags)) {
+ bh_unlock_sock(sk_atm(vcc));
+ kfree_skb(skb);
+ return DROP_PACKET;
+ }
switch (pvcc->encaps) { /* LLC encapsulation needed */
case e_llc:

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