From 79a5b9727a1cceacd49921b78425ebda91836bd6 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Thu, 22 Feb 2018 13:40:27 -0800 Subject: 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: 0cebaccef3ac ("rds: zerocopy Tx support.") Signed-off-by: Sowmini Varadhan Acked-by: Willem de Bruijn Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller --- net/rds/send.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/rds/send.c b/net/rds/send.c index 79d158b3def0..acad04243b41 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -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; -- cgit v1.2.3