[PATCH net-next v2] sctp: fix error return code in sctp_sendmsg_new_asoc()

[Wei Yongjun]

Return error code -EINVAL in the address len check error handling
case since 'err' can be overwrite to 0 by 'err = sctp_verify_addr()'
in the for loop.

Fixes: 2c0dbaa0c43d ("sctp: add support for SCTP_DSTADDRV4/6 Information for 
sendmsg")
Signed-off-by: Wei Yongjun <weiyongj...@huawei.com>
Acked-by: Neil Horman <nhor...@tuxdriver.com>
---
v1 -> v2: remove the 'err' initialization
---
 net/sctp/socket.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 7d3476a..af5cf29 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1677,7 +1677,7 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 
sflags,
        struct sctp_association *asoc;
        enum sctp_scope scope;
        struct cmsghdr *cmsg;
-       int err = -EINVAL;
+       int err;
 
        *tp = NULL;
 
@@ -1761,16 +1761,20 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 
sflags,
                memset(daddr, 0, sizeof(*daddr));
                dlen = cmsg->cmsg_len - sizeof(struct cmsghdr);
                if (cmsg->cmsg_type == SCTP_DSTADDRV4) {
-                       if (dlen < sizeof(struct in_addr))
+                       if (dlen < sizeof(struct in_addr)) {
+                               err = -EINVAL;
                                goto free;
+                       }
 
                        dlen = sizeof(struct in_addr);
                        daddr->v4.sin_family = AF_INET;
                        daddr->v4.sin_port = htons(asoc->peer.port);
                        memcpy(&daddr->v4.sin_addr, CMSG_DATA(cmsg), dlen);
                } else {
-                       if (dlen < sizeof(struct in6_addr))
+                       if (dlen < sizeof(struct in6_addr)) {
+                               err = -EINVAL;
                                goto free;
+                       }
 
                        dlen = sizeof(struct in6_addr);
                        daddr->v6.sin6_family = AF_INET6;