From ac4340fc3ce0e0b1cb627b05d6dcbd473544d7b3 Mon Sep 17 00:00:00 2001 From: David S. Miller Date: Wed, 4 Jan 2017 13:24:19 -0500 Subject: net: Assert at build time the assumptions we make about the CMSG header. It must always be the case that CMSG_ALIGN(sizeof(hdr)) == sizeof(hdr). Otherwise there are missing adjustments in the various calculations that parse and build these things. Signed-off-by: David S. Miller --- net/socket.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/socket.c') diff --git a/net/socket.c b/net/socket.c index 8487bf136e5c..5f3b5a2c4f37 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1948,6 +1948,8 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, ctl_buf = msg_sys->msg_control; ctl_len = msg_sys->msg_controllen; } else if (ctl_len) { + BUILD_BUG_ON(sizeof(struct cmsghdr) != + CMSG_ALIGN(sizeof(struct cmsghdr))); if (ctl_len > sizeof(ctl)) { ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL); if (ctl_buf == NULL) -- cgit v1.2.3-55-g7522