From 84602761ca4495dd409be936dfa93ed20c946684 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Fri, 27 Dec 2013 10:18:28 +0800 Subject: tipc: fix deadlock during socket release A deadlock might occur if name table is withdrawn in socket release routine, and while packets are still being received from bearer. CPU0 CPU1 T0: recv_msg() release() T1: tipc_recv_msg() tipc_withdraw() T2: [grab node lock] [grab port lock] T3: tipc_link_wakeup_ports() tipc_nametbl_withdraw() T4: [grab port lock]* named_cluster_distribute() T5: wakeupdispatch() tipc_link_send() T6: [grab node lock]* The opposite order of holding port lock and node lock on above two different paths may result in a deadlock. If socket lock instead of port lock is used to protect port instance in tipc_withdraw(), the reverse order of holding port lock and node lock will be eliminated, as a result, the deadlock is killed as well. Reported-by: Lars Everbrand Reviewed-by: Erik Hugne Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/port.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'net/tipc/port.h') diff --git a/net/tipc/port.h b/net/tipc/port.h index 91225359734..34f12bd4074 100644 --- a/net/tipc/port.h +++ b/net/tipc/port.h @@ -116,7 +116,7 @@ int tipc_reject_msg(struct sk_buff *buf, u32 err); void tipc_acknowledge(u32 port_ref, u32 ack); -int tipc_deleteport(u32 portref); +int tipc_deleteport(struct tipc_port *p_ptr); int tipc_portimportance(u32 portref, unsigned int *importance); int tipc_set_portimportance(u32 portref, unsigned int importance); @@ -127,9 +127,9 @@ int tipc_set_portunreliable(u32 portref, unsigned int isunreliable); int tipc_portunreturnable(u32 portref, unsigned int *isunreturnable); int tipc_set_portunreturnable(u32 portref, unsigned int isunreturnable); -int tipc_publish(u32 portref, unsigned int scope, +int tipc_publish(struct tipc_port *p_ptr, unsigned int scope, struct tipc_name_seq const *name_seq); -int tipc_withdraw(u32 portref, unsigned int scope, +int tipc_withdraw(struct tipc_port *p_ptr, unsigned int scope, struct tipc_name_seq const *name_seq); int tipc_connect(u32 portref, struct tipc_portid const *port); -- cgit v1.2.3-70-g09d2