From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
commit f19425641cb2572a33cb074d5e30283720bd4d22 upstream.
Only sockets will have the chan->data set to an actual sk, channels
like A2MP would have its own data which would likely cause a crash when
calling sk_filter, in order to fix this a new callback has been
introduced so channels can implement their own filtering if necessary.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/net/bluetooth/l2cap.h | 2 ++
net/bluetooth/l2cap_core.c | 7 ++++---
net/bluetooth/l2cap_sock.c | 14 ++++++++++++++
3 files changed, 20 insertions(+), 3 deletions(-)
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -623,6 +623,8 @@ struct l2cap_ops {
struct sk_buff *(*alloc_skb) (struct l2cap_chan *chan,
unsigned long hdr_len,
unsigned long len, int nb);
+ int (*filter) (struct l2cap_chan * chan,
+ struct sk_buff *skb);
};
struct l2cap_conn {
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -6701,9 +6701,10 @@ static int l2cap_data_rcv(struct l2cap_c
goto drop;
}
- if ((chan->mode == L2CAP_MODE_ERTM ||
- chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
- goto drop;
+ if (chan->ops->filter) {
+ if (chan->ops->filter(chan, skb))
+ goto drop;
+ }
if (!control->sframe) {
int err;
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1479,6 +1479,19 @@ static void l2cap_sock_suspend_cb(struct
sk->sk_state_change(sk);
}
+static int l2cap_sock_filter(struct l2cap_chan *chan, struct sk_buff *skb)
+{
+ struct sock *sk = chan->data;
+
+ switch (chan->mode) {
+ case L2CAP_MODE_ERTM:
+ case L2CAP_MODE_STREAMING:
+ return sk_filter(sk, skb);
+ }
+
+ return 0;
+}
+
static const struct l2cap_ops l2cap_chan_ops = {
.name = "L2CAP Socket Interface",
.new_connection = l2cap_sock_new_connection_cb,
@@ -1493,6 +1506,7 @@ static const struct l2cap_ops l2cap_chan
.set_shutdown = l2cap_sock_set_shutdown_cb,
.get_sndtimeo = l2cap_sock_get_sndtimeo_cb,
.alloc_skb = l2cap_sock_alloc_skb_cb,
+ .filter = l2cap_sock_filter,
};
static void l2cap_sock_destruct(struct sock *sk)
