packet_diag: disclose uid value

This value is disclosed via /proc/net/packet but not via netlink messages.
The goal is to have the same level of information.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 5 deletions

diff --git a/net/packet/diag.c b/net/packet/diag.c
index d3fcd1ebef7e..04c8219a2d06 100644
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -125,8 +125,10 @@ static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
         return ret;
 }
 
-static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct packet_diag_req *req,
-                u32 portid, u32 seq, u32 flags, int sk_ino)
+static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
+                        struct packet_diag_req *req,
+                        struct user_namespace *user_ns,
+                        u32 portid, u32 seq, u32 flags, int sk_ino)
 {
         struct nlmsghdr *nlh;
         struct packet_diag_msg *rp;
@@ -147,6 +149,11 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct packet_diag
                         pdiag_put_info(po, skb))
                 goto out_nlmsg_trim;
 
+        if ((req->pdiag_show & PACKET_SHOW_INFO) &&
+            nla_put_u32(skb, PACKET_DIAG_UID,
+                        from_kuid_munged(user_ns, sock_i_uid(sk))))
+                goto out_nlmsg_trim;
+
         if ((req->pdiag_show & PACKET_SHOW_MCLIST) &&
                         pdiag_put_mclist(po, skb))
                 goto out_nlmsg_trim;
@@ -183,9 +190,11 @@ static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
                 if (num < s_num)
                         goto next;
 
-                if (sk_diag_fill(sk, skb, req, NETLINK_CB(cb->skb).portid,
-                                        cb->nlh->nlmsg_seq, NLM_F_MULTI,
-                                        sock_i_ino(sk)) < 0)
+                if (sk_diag_fill(sk, skb, req,
+                                 sk_user_ns(NETLINK_CB(cb->skb).sk),
+                                 NETLINK_CB(cb->skb).portid,
+                                 cb->nlh->nlmsg_seq, NLM_F_MULTI,
+                                 sock_i_ino(sk)) < 0)
                         goto done;
 next:
                 num++;