[net-next,1/2] samples/bpf: fix SKB_MODE flag to be a 32-bit unsigned int

The kernel side of XDP_FLAGS_SKB_MODE is unsigned, and the rtnetlink
IFLA_XDP_FLAGS is defined as NLA_U32. Thus, userspace programs under
samples/bpf/ should use the correct type.

Fixes: 3993f2cb983b ("samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 samples/bpf/bpf_load.c             |    3 ++-
 samples/bpf/bpf_load.h             |    2 +-
 samples/bpf/xdp1_user.c            |    8 ++++----
 samples/bpf/xdp_tx_iptunnel_user.c |    8 ++++----
 4 files changed, 11 insertions(+), 10 deletions(-)

On 05/01/2017 11:26 AM, Jesper Dangaard Brouer wrote:
> The kernel side of XDP_FLAGS_SKB_MODE is unsigned, and the rtnetlink
> IFLA_XDP_FLAGS is defined as NLA_U32. Thus, userspace programs under
> samples/bpf/ should use the correct type.
>
> Fixes: 3993f2cb983b ("samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel")
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

On Mon, May 01, 2017 at 11:26:15AM +0200, Jesper Dangaard Brouer wrote:
> The kernel side of XDP_FLAGS_SKB_MODE is unsigned, and the rtnetlink
> IFLA_XDP_FLAGS is defined as NLA_U32. Thus, userspace programs under
> samples/bpf/ should use the correct type.
> 
> Fixes: 3993f2cb983b ("samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel")
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Reviewed-by: Andy Gospodarek <andy@greyhouse.net>

> ---
>  samples/bpf/bpf_load.c             |    3 ++-
>  samples/bpf/bpf_load.h             |    2 +-
>  samples/bpf/xdp1_user.c            |    8 ++++----
>  samples/bpf/xdp_tx_iptunnel_user.c |    8 ++++----
>  4 files changed, 11 insertions(+), 10 deletions(-)
> 
> diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
> index 0ec0dea3c41e..4221dc359453 100644
> --- a/samples/bpf/bpf_load.c
> +++ b/samples/bpf/bpf_load.c
> @@ -14,6 +14,7 @@
>  #include <linux/perf_event.h>
>  #include <linux/netlink.h>
>  #include <linux/rtnetlink.h>
> +#include <linux/types.h>
>  #include <sys/types.h>
>  #include <sys/socket.h>
>  #include <sys/syscall.h>
> @@ -585,7 +586,7 @@ struct ksym *ksym_search(long key)
>  	return &syms[0];
>  }
>  
> -int set_link_xdp_fd(int ifindex, int fd, int flags)
> +int set_link_xdp_fd(int ifindex, int fd, __u32 flags)
>  {
>  	struct sockaddr_nl sa;
>  	int sock, seq = 0, len, ret = -1;
> diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
> index 6bfd75ec6a16..05822f83173a 100644
> --- a/samples/bpf/bpf_load.h
> +++ b/samples/bpf/bpf_load.h
> @@ -47,5 +47,5 @@ struct ksym {
>  
>  int load_kallsyms(void);
>  struct ksym *ksym_search(long key);
> -int set_link_xdp_fd(int ifindex, int fd, int flags);
> +int set_link_xdp_fd(int ifindex, int fd, __u32 flags);
>  #endif
> diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
> index deb05e630d84..378850c70eb8 100644
> --- a/samples/bpf/xdp1_user.c
> +++ b/samples/bpf/xdp1_user.c
> @@ -20,11 +20,11 @@
>  #include "libbpf.h"
>  
>  static int ifindex;
> -static int flags;
> +static __u32 xdp_flags;
>  
>  static void int_exit(int sig)
>  {
> -	set_link_xdp_fd(ifindex, -1, flags);
> +	set_link_xdp_fd(ifindex, -1, xdp_flags);
>  	exit(0);
>  }
>  
> @@ -75,7 +75,7 @@ int main(int argc, char **argv)
>  	while ((opt = getopt(argc, argv, optstr)) != -1) {
>  		switch (opt) {
>  		case 'S':
> -			flags |= XDP_FLAGS_SKB_MODE;
> +			xdp_flags |= XDP_FLAGS_SKB_MODE;
>  			break;
>  		default:
>  			usage(basename(argv[0]));
> @@ -103,7 +103,7 @@ int main(int argc, char **argv)
>  
>  	signal(SIGINT, int_exit);
>  
> -	if (set_link_xdp_fd(ifindex, prog_fd[0], flags) < 0) {
> +	if (set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
>  		printf("link set xdp fd failed\n");
>  		return 1;
>  	}
> diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
> index cb2bda7b5346..880dd4aebfa4 100644
> --- a/samples/bpf/xdp_tx_iptunnel_user.c
> +++ b/samples/bpf/xdp_tx_iptunnel_user.c
> @@ -142,8 +142,8 @@ int main(int argc, char **argv)
>  	struct iptnl_info tnl = {};
>  	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
>  	struct vip vip = {};
> +	__u32 xdp_flags = 0;
>  	char filename[256];
> -	int flags = 0;
>  	int opt;
>  	int i;
>  
> @@ -204,7 +204,7 @@ int main(int argc, char **argv)
>  			kill_after_s = atoi(optarg);
>  			break;
>  		case 'S':
> -			flags |= XDP_FLAGS_SKB_MODE;
> +			xdp_flags |= XDP_FLAGS_SKB_MODE;
>  			break;
>  		default:
>  			usage(argv[0]);
> @@ -248,14 +248,14 @@ int main(int argc, char **argv)
>  		}
>  	}
>  
> -	if (set_link_xdp_fd(ifindex, prog_fd[0], flags) < 0) {
> +	if (set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
>  		printf("link set xdp fd failed\n");
>  		return 1;
>  	}
>  
>  	poll_stats(kill_after_s);
>  
> -	set_link_xdp_fd(ifindex, -1, flags);
> +	set_link_xdp_fd(ifindex, -1, xdp_flags);
>  
>  	return 0;
>  }