rds: rds_msg_zcopy should return error of null rm->data.op_mmp_znotifier

if either or both of MSG_ZEROCOPY and SOCK_ZEROCOPY have not been
specified, the rm->data.op_mmp_znotifier allocation will be skipped.
In this case, it is invalid ot pass down a cmsghdr with
RDS_CMSG_ZCOPY_COOKIE, so return EINVAL from rds_msg_zcopy for this
case.

Reported-by: syzbot+f893ae7bb2f6456dfbc3@syzkaller.appspotmail.com
Fixes: 0cebaccef3 ("rds: zerocopy Tx support.")
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sowmini Varadhan 2018-02-22 13:40:27 -08:00 committed by David S. Miller
parent 9dbe7896d9
commit 79a5b9727a
1 changed files with 2 additions and 1 deletions

View File

@ -941,7 +941,8 @@ static int rds_cmsg_zcopy(struct rds_sock *rs, struct rds_message *rm,
{
u32 *cookie;
if (cmsg->cmsg_len < CMSG_LEN(sizeof(*cookie)))
if (cmsg->cmsg_len < CMSG_LEN(sizeof(*cookie)) ||
!rm->data.op_mmp_znotifier)
return -EINVAL;
cookie = CMSG_DATA(cmsg);
rm->data.op_mmp_znotifier->z_cookie = *cookie;