From: Nick Pelly Date: Thu, 4 Feb 2010 00:18:36 +0000 (-0800) Subject: Bluetooth: Do not call rfcomm_session_put() for RFCOMM UA on closed socket X-Git-Tag: MMI-PSA29.97-13-9~24944^2~14^2~3 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6c2718d;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git Bluetooth: Do not call rfcomm_session_put() for RFCOMM UA on closed socket When processing a RFCOMM UA frame when the socket is closed and we were not the RFCOMM initiator would cause rfcomm_session_put() to be called twice during rfcomm_process_rx(). This would cause a kernel panic in rfcomm_session_close() then. This could be easily reproduced during disconnect with devices such as Motorola H270 that send RFCOMM UA followed quickly by L2CAP disconnect request. This trace for this looks like: 2009-09-21 17:22:37.788895 < ACL data: handle 1 flags 0x02 dlen 8 L2CAP(d): cid 0x0041 len 4 [psm 3] RFCOMM(s): DISC: cr 0 dlci 20 pf 1 ilen 0 fcs 0x7d 2009-09-21 17:22:37.906204 > HCI Event: Number of Completed Packets (0x13) plen 5 handle 1 packets 1 2009-09-21 17:22:37.933090 > ACL data: handle 1 flags 0x02 dlen 8 L2CAP(d): cid 0x0040 len 4 [psm 3] RFCOMM(s): UA: cr 0 dlci 20 pf 1 ilen 0 fcs 0x57 2009-09-21 17:22:38.636764 < ACL data: handle 1 flags 0x02 dlen 8 L2CAP(d): cid 0x0041 len 4 [psm 3] RFCOMM(s): DISC: cr 0 dlci 0 pf 1 ilen 0 fcs 0x9c 2009-09-21 17:22:38.744125 > HCI Event: Number of Completed Packets (0x13) plen 5 handle 1 packets 1 2009-09-21 17:22:38.763687 > ACL data: handle 1 flags 0x02 dlen 8 L2CAP(d): cid 0x0040 len 4 [psm 3] RFCOMM(s): UA: cr 0 dlci 0 pf 1 ilen 0 fcs 0xb6 2009-09-21 17:22:38.783554 > ACL data: handle 1 flags 0x02 dlen 12 L2CAP(s): Disconn req: dcid 0x0040 scid 0x0041 Avoid calling rfcomm_session_put() twice by skipping this call in rfcomm_recv_ua() if the socket is closed. Signed-off-by: Nick Pelly Signed-off-by: Marcel Holtmann --- diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c index 2b506373957a..89f4a59eb82b 100644 --- a/net/bluetooth/rfcomm/core.c +++ b/net/bluetooth/rfcomm/core.c @@ -1150,7 +1150,11 @@ static int rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci) break; case BT_DISCONN: - rfcomm_session_put(s); + /* When socket is closed and we are not RFCOMM + * initiator rfcomm_process_rx already calls + * rfcomm_session_put() */ + if (s->sock->sk->sk_state != BT_CLOSED) + rfcomm_session_put(s); break; } }