[Fix kernel crash in cipso_v4_sock_delattr ]

[Maninder Singh]

Dear All,
we found One Kernel Crash issue in cipso_v4_sock_delattr :-
As Cipso supports only inet sockets so cipso_v4_sock_delattr will crash when try to access
any other socket type.  cipso_v4_sock_delattr access sk_inet->inet_opt which may
contain not NULL but invalid address. we found this issue with netlink socket.(reproducible by trinity using sendto system call .)

Crash Logs :
[0-182.2400] [<c04c7fa4>] (cipso_v4_sock_delattr+0x0/0x74) from [<c0517b64>] (netlbl_sock_delattr+0x18/0x1c)
[0-182.2497]  r4:00000000 r3:c07872f8
[0-182.2531] [<c0517b4c>] (netlbl_sock_delattr+0x0/0x1c) from [<c027b2fc>] (smack_netlabel+0x88/0x9c)
[0-182.2622] [<c027b274>] (smack_netlabel+0x0/0x9c) from [<c027b43c>] (smack_netlabel_send+0x12c/0x144)
[0-182.2714]  r7 9ce9500 r6 7b67ef4 r5:c076f408 r4 8903dc0
[0-182.2770] [<c027b310>] (smack_netlabel_send+0x0/0x144) from [<c027b4a8>] (smack_socket_sendmsg+0x54/0x60)
[0-182.2866] [<c027b454>] (smack_socket_sendmsg+0x0/0x60) from [<c02789ec>] (security_socket_sendmsg+0x28/0x2c)
[0-182.2966] [<c02789c4>] (security_socket_sendmsg+0x0/0x2c) from [<c04343b0>] (sock_sendmsg+0x68/0xc0)
[0-182.3058] [<c0434348>] (sock_sendmsg+0x0/0xc0) from [<c04369e8>] (SyS_sendto+0xd8/0x110)
Signed-off-by: Vaneet Narang <v.narang@xxxxxxxxxxx>
Signed-off-by: Maninder Singh <maninder1.s@xxxxxxxxxxx>
Reviewed-by : Ajeet Yadav <ajeet.y@xxxxxxxxxxx>
---
 net/netlabel/netlabel_kapi.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index 7c94aed..7a2c6f5 100755
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -700,7 +700,13 @@ socket_setattr_return:
  */
 void netlbl_sock_delattr(struct sock *sk)
 {
- cipso_v4_sock_delattr(sk);
+ switch (sk->sk_family) {
+ case AF_INET:
+  cipso_v4_sock_delattr(sk);
+  break;
+ default:
+  break;
+ }
 }
 
 /**
-- 
1.7.9.5


Thanks and Regards,
Maninder Singh