4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Cong Wang xiyou.wangcong@gmail.com
[ Upstream commit 3c6306d44082ef007a258ae1b86ea58e6974ee3f ]
Similar to commit 143ece654f9f ("tipc: check tsk->group in tipc_wait_for_cond()") we have to reload grp->dests too after we re-take the sock lock. This means we need to move the dsts check after tipc_wait_for_cond() too.
Fixes: 75da2163dbb6 ("tipc: introduce communication groups") Reported-and-tested-by: syzbot+99f20222fc5018d2b97a@syzkaller.appspotmail.com Cc: Ying Xue ying.xue@windriver.com Cc: Jon Maloy jon.maloy@ericsson.com Signed-off-by: Cong Wang xiyou.wangcong@gmail.com Acked-by: Jon Maloy jon.maloy@ericsson.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/tipc/socket.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
--- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -1007,7 +1007,7 @@ static int tipc_send_group_bcast(struct struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct tipc_sock *tsk = tipc_sk(sk); - struct tipc_nlist *dsts = tipc_group_dests(tsk->group); + struct tipc_nlist *dsts; struct tipc_mc_method *method = &tsk->mc_method; bool ack = method->mandatory && method->rcast; int blks = tsk_blocks(MCAST_H_SIZE + dlen); @@ -1016,9 +1016,6 @@ static int tipc_send_group_bcast(struct struct sk_buff_head pkts; int rc = -EHOSTUNREACH;
- if (!dsts->local && !dsts->remote) - return -EHOSTUNREACH; - /* Block or return if any destination link or member is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt && tsk->group && @@ -1026,6 +1023,10 @@ static int tipc_send_group_bcast(struct if (unlikely(rc)) return rc;
+ dsts = tipc_group_dests(tsk->group); + if (!dsts->local && !dsts->remote) + return -EHOSTUNREACH; + /* Complete message header */ if (dest) { msg_set_type(hdr, TIPC_GRP_MCAST_MSG);