netlink: extend buffers to 16K

Starting from linux-3.15 (commit 9063e21fb026, "netlink: autosize skb
lengths"), kernel is able to send up to 16K in netlink replies.

This change enables iproute2 commands to get bigger chunks,
without breaking compatibility with old kernels.

Signed-off-by: Eric Dumazet <edumazet@google.com>

diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index 9e2a7958e9dd4ec558c224cab33dd79db7b7dc77..8d504a9e769bd5eb29e9d97754acfec6fa7ecca2 100644 (file)
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c
@@ -420,7 +420,7 @@ int rtnl_listen(struct rtnl_handle *rtnl,
                .msg_iov = &iov,
                .msg_iovlen = 1,
        };
-       char   buf[8192];
+       char   buf[16384];
 
        memset(&nladdr, 0, sizeof(nladdr));
        nladdr.nl_family = AF_NETLINK;
@@ -486,7 +486,7 @@ int rtnl_from_file(FILE *rtnl, rtnl_filter_t handler,
 {
        int status;
        struct sockaddr_nl nladdr;
-       char   buf[8192];
+       char   buf[16384];
        struct nlmsghdr *h = (void*)buf;
 
        memset(&nladdr, 0, sizeof(nladdr));

diff --git a/misc/ss.c b/misc/ss.c
index d3c4fa6597ba62d9a106a56fcc4b753e49f37b75..b7e0ef00bf1ab2c8f71760b371fb4ff8cb1ee40c 100644 (file)
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -1877,7 +1877,7 @@ static int inet_show_netlink(struct filter *f, FILE *dump_fp, int protocol)
        int fd, family;
        struct sockaddr_nl nladdr;
        struct msghdr msg;
-       char    buf[8192];
+       char    buf[16384];
        struct iovec iov[3];
 
        if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_INET_DIAG)) < 0)
@@ -1993,7 +1993,7 @@ done:
 static int tcp_show_netlink_file(struct filter *f)
 {
        FILE    *fp;
-       char    buf[8192];
+       char    buf[16384];
 
        if ((fp = fopen(getenv("TCPDIAG_FILE"), "r")) == NULL) {
                perror("fopen($TCPDIAG_FILE)");
@@ -2510,7 +2510,7 @@ static int handle_netlink_request(struct filter *f, FILE *dump_fp,
                                  int (* show_one_sock)(struct nlmsghdr *nlh, struct filter *f))
 {
        int fd;
-       char    buf[8192];
+       char    buf[16384];
 
        if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_INET_DIAG)) < 0)
                return -1;
@@ -2795,7 +2795,7 @@ static int packet_show_netlink(struct filter *f, FILE *dump_fp)
                struct nlmsghdr nlh;
                struct packet_diag_req r;
        } req;
-       char    buf[8192];
+       char    buf[16384];
 
        if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_INET_DIAG)) < 0)
                return -1;