2 files changed, 42 insertions, 0 deletions

diff --git a/include/uapi/linux/netlink_diag.h b/include/uapi/linux/netlink_diag.h
index 88009a31cd06..4e31db4eea41 100644
--- a/include/uapi/linux/netlink_diag.h
+++ b/include/uapi/linux/netlink_diag.h
@@ -25,9 +25,18 @@ struct netlink_diag_msg {
         __u32   ndiag_cookie[2];
 };
 
+struct netlink_diag_ring {
+        __u32   ndr_block_size;
+        __u32   ndr_block_nr;
+        __u32   ndr_frame_size;
+        __u32   ndr_frame_nr;
+};
+
 enum {
         NETLINK_DIAG_MEMINFO,
         NETLINK_DIAG_GROUPS,
+        NETLINK_DIAG_RX_RING,
+        NETLINK_DIAG_TX_RING,
 
         __NETLINK_DIAG_MAX,
 };
@@ -38,5 +47,6 @@ enum {
 
 #define NDIAG_SHOW_MEMINFO      0x00000001 /* show memory info of a socket */
 #define NDIAG_SHOW_GROUPS       0x00000002 /* show groups of a netlink socket */
+#define NDIAG_SHOW_RING_CFG     0x00000004 /* show ring configuration */
 
 #endif
diff --git a/net/netlink/diag.c b/net/netlink/diag.c
index 5ffb1d1cf402..4e4aa471cd05 100644
--- a/net/netlink/diag.c
+++ b/net/netlink/diag.c
@@ -7,6 +7,34 @@
 
 #include "af_netlink.h"
 
+static int sk_diag_put_ring(struct netlink_ring *ring, int nl_type,
+                            struct sk_buff *nlskb)
+{
+        struct netlink_diag_ring ndr;
+
+        ndr.ndr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
+        ndr.ndr_block_nr   = ring->pg_vec_len;
+        ndr.ndr_frame_size = ring->frame_size;
+        ndr.ndr_frame_nr   = ring->frame_max + 1;
+
+        return nla_put(nlskb, nl_type, sizeof(ndr), &ndr);
+}
+
+static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
+{
+        struct netlink_sock *nlk = nlk_sk(sk);
+        int ret;
+
+        mutex_lock(&nlk->pg_vec_lock);
+        ret = sk_diag_put_ring(&nlk->rx_ring, NETLINK_DIAG_RX_RING, nlskb);
+        if (!ret)
+                ret = sk_diag_put_ring(&nlk->tx_ring, NETLINK_DIAG_TX_RING,
+                                       nlskb);
+        mutex_unlock(&nlk->pg_vec_lock);
+
+        return ret;
+}
+
 static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
 {
         struct netlink_sock *nlk = nlk_sk(sk);
@@ -51,6 +79,10 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
             sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
                 goto out_nlmsg_trim;
 
+        if ((req->ndiag_show & NDIAG_SHOW_RING_CFG) &&
+            sk_diag_put_rings_cfg(sk, skb))
+                goto out_nlmsg_trim;
+
         return nlmsg_end(skb, nlh);
 
 out_nlmsg_trim: