From: Dmitry V. Levin ldv@altlinux.org

commit a725eb15db80643a160310ed6bcfd6c5a6c907f2 upstream.

Because of <linux/libc-compat.h> interface limitations, <netinet/in.h> provided by libc cannot be included after <linux/in.h>, therefore any header that includes <netinet/in.h> cannot be included after <linux/in.h>.

Change uapi/linux/l2tp.h, the last uapi header that includes <netinet/in.h>, to include <linux/in.h> and <linux/in6.h> instead of <netinet/in.h> and use __SOCK_SIZE__ instead of sizeof(struct sockaddr) the same way as uapi/linux/in.h does, to fix linux/if_pppol2tp.h userspace compilation errors like this:

In file included from /usr/include/linux/l2tp.h:12:0, from /usr/include/linux/if_pppol2tp.h:21, /usr/include/netinet/in.h:31:8: error: redefinition of 'struct in_addr'

Fixes: cc84b4ddee15 ("net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*") Signed-off-by: Dmitry V. Levin ldv@altlinux.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Asbjoern Sloth Toennesen asbjorn@asbjorn.st ---

Notes: Sorry for not submitting this in the review cycle, was waiting for a response to my initial mail, when the cycle was cut short, had planned to reply to the review if I hadn't got a reply half way through it.

https://lore.kernel.org/stable/25373712-4390-5a7a-d3f9-97bd7f2d8a2a@asbjorn....

I was unsure which commit, to put in Fixes:, ended up with the stable commit, and not the one from mainline. I hope that's correct.

Original patch thread: https://lore.kernel.org/netdev/20170214103353.GA8394@altlinux.org/

include/uapi/linux/l2tp.h | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/l2tp.h b/include/uapi/linux/l2tp.h index bb2d62037037..80d85053fb06 100644 --- a/include/uapi/linux/l2tp.h +++ b/include/uapi/linux/l2tp.h @@ -9,9 +9,8 @@

#include <linux/types.h> #include <linux/socket.h> -#ifndef __KERNEL__ -#include <netinet/in.h> -#endif +#include <linux/in.h> +#include <linux/in6.h>

#define IPPROTO_L2TP 115

@@ -31,7 +30,7 @@ struct sockaddr_l2tpip { __u32 l2tp_conn_id; /* Connection ID of tunnel */

/* Pad to size of `struct sockaddr'. */ - unsigned char __pad[sizeof(struct sockaddr) - + unsigned char __pad[__SOCK_SIZE__ - sizeof(__kernel_sa_family_t) - sizeof(__be16) - sizeof(struct in_addr) - sizeof(__u32)];