diff options
author | Eric Dumazet <edumazet@google.com> | 2017-02-12 14:03:52 -0800 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2017-03-16 02:18:49 +0000 |
commit | 0887b3f35f6ff8826c24572d91e2adbea965d4e6 (patch) | |
tree | 2623efa525f22dbafb1363ff497e8eb27421da1f /net | |
parent | 76f6adf05c7682a090a8bb738a728e90e0130959 (diff) |
net/llc: avoid BUG_ON() in skb_orphan()
commit 8b74d439e1697110c5e5c600643e823eb1dd0762 upstream.
It seems nobody used LLC since linux-3.12.
Fortunately fuzzers like syzkaller still know how to run this code,
otherwise it would be no fun.
Setting skb->sk without skb->destructor leads to all kinds of
bugs, we now prefer to be very strict about it.
Ideally here we would use skb_set_owner() but this helper does not exist yet,
only CAN seems to have a private helper for that.
Fixes: 376c7311bdb6 ("net: add a temporary sanity check in skb_orphan()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net')
-rw-r--r-- | net/llc/llc_conn.c | 3 | ||||
-rw-r--r-- | net/llc/llc_sap.c | 3 |
2 files changed, 6 insertions, 0 deletions
diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c index ba137a6a224d..f3125b92c3e8 100644 --- a/net/llc/llc_conn.c +++ b/net/llc/llc_conn.c @@ -821,7 +821,10 @@ void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb) * another trick required to cope with how the PROCOM state * machine works. -acme */ + skb_orphan(skb); + sock_hold(sk); skb->sk = sk; + skb->destructor = sock_efree; } if (!sock_owned_by_user(sk)) llc_conn_rcv(sk, skb); diff --git a/net/llc/llc_sap.c b/net/llc/llc_sap.c index 94e7fca75b85..687fe7409e15 100644 --- a/net/llc/llc_sap.c +++ b/net/llc/llc_sap.c @@ -294,7 +294,10 @@ static void llc_sap_rcv(struct llc_sap *sap, struct sk_buff *skb, ev->type = LLC_SAP_EV_TYPE_PDU; ev->reason = 0; + skb_orphan(skb); + sock_hold(sk); skb->sk = sk; + skb->destructor = sock_efree; llc_sap_state_process(sap, skb); } |