tipc: fix missing initializer in tipc_sendmsg()

The stack variable 'dnode' in __tipc_sendmsg() may theoretically
end up tipc_node_get_mtu() as an unitilalized variable.

We fix this by intializing the variable at declaration. We also add
a default else clause to the two conditional ones already there, so
that we never end up in the named function if the given address
type is illegal.

Reported-by: syzbot+b0975ce9355b347c1546@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jon Maloy 2018-04-12 01:15:48 +02:00 committed by David S. Miller
parent 9d0c75bf6e
commit 335b929b28

View File

@ -1278,7 +1278,7 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
struct tipc_msg *hdr = &tsk->phdr; struct tipc_msg *hdr = &tsk->phdr;
struct tipc_name_seq *seq; struct tipc_name_seq *seq;
struct sk_buff_head pkts; struct sk_buff_head pkts;
u32 dnode, dport; u32 dport, dnode = 0;
u32 type, inst; u32 type, inst;
int mtu, rc; int mtu, rc;
@ -1348,6 +1348,8 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
msg_set_destnode(hdr, dnode); msg_set_destnode(hdr, dnode);
msg_set_destport(hdr, dest->addr.id.ref); msg_set_destport(hdr, dest->addr.id.ref);
msg_set_hdr_sz(hdr, BASIC_H_SIZE); msg_set_hdr_sz(hdr, BASIC_H_SIZE);
} else {
return -EINVAL;
} }
/* Block or return if destination link is congested */ /* Block or return if destination link is congested */