[PATCH 3/5] Export the udp sock's security context to proc.

[<rongqing.li@windriver.com>]

From: Roy.Li <rongqing.li@windriver.com>

Export the udp sock's security context to proc, since it maybe
different from the sock's owner process security context.

Signed-off-by: Roy.Li <rongqing.li@windriver.com>
---
 net/ipv4/udp.c |   19 ++++++++++++++-----
 1 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 1b5a193..e64b858 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2089,6 +2089,7 @@ static void udp4_format_sock(struct sock *sp, struct seq_file *f,
 		int bucket, int *len)
 {
 	struct inet_sock *inet = inet_sk(sp);
+	int sclen;
 	__be32 dest = inet->inet_daddr;
 	__be32 src  = inet->inet_rcv_saddr;
 	__u16 destp	  = ntohs(inet->inet_dport);
@@ -2102,21 +2103,29 @@ static void udp4_format_sock(struct sock *sp, struct seq_file *f,
 		0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
 		atomic_read(&sp->sk_refcnt), sp,
 		atomic_read(&sp->sk_drops), len);
+
+	sock_write_secctx(sp, f, &sclen);
+	*len += sclen;
 }
 
 int udp4_seq_show(struct seq_file *seq, void *v)
 {
-	if (v == SEQ_START_TOKEN)
-		seq_printf(seq, "%-127s\n",
+	int len;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_printf(seq,
 			   "  sl  local_address rem_address   st tx_queue "
 			   "rx_queue tr tm->when retrnsmt   uid  timeout "
-			   "inode ref pointer drops");
+			   "inode ref pointer drops%n",
+			   &len);
+		seq_printf(seq, "%-*s\n", 150 - len,
+			   (selinux_is_enabled() ? "  scontext" : ""));
+	}
 	else {
 		struct udp_iter_state *state = seq->private;
-		int len;
 
 		udp4_format_sock(v, seq, state->bucket, &len);
-		seq_printf(seq, "%*s\n", 127 - len, "");
+		seq_printf(seq, "%*s\n", 150 - len, "");
 	}
 	return 0;
 }
-- 
1.7.1