net: check both type and procotol for tcp sockets

Dmitry reported the following out-of-bound access:

Call Trace:
 [<ffffffff816cec2e>] __asan_report_load4_noabort+0x3e/0x40
mm/kasan/report.c:294
 [<ffffffff84affb14>] sock_setsockopt+0x1284/0x13d0 net/core/sock.c:880
 [<     inline     >] SYSC_setsockopt net/socket.c:1746
 [<ffffffff84aed7ee>] SyS_setsockopt+0x1fe/0x240 net/socket.c:1729
 [<ffffffff85c18c76>] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185

This is because we mistake a raw socket as a tcp socket.
We should check both sk->sk_type and sk->sk_protocol to ensure
it is a tcp socket.

Willem points out __skb_complete_tx_timestamp() needs to fix as well.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 5cc43d3..b2df375 100644 (file)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3643,7 +3643,8 @@ static void __skb_complete_tx_timestamp(struct sk_buff *skb,
        serr->ee.ee_info = tstype;
        if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) {
                serr->ee.ee_data = skb_shinfo(skb)->tskey;
-               if (sk->sk_protocol == IPPROTO_TCP)
+               if (sk->sk_protocol == IPPROTO_TCP &&
+                   sk->sk_type == SOCK_STREAM)
                        serr->ee.ee_data -= sk->sk_tskey;
        }
 

diff --git a/net/core/sock.c b/net/core/sock.c
index 765be83..0d91f7d 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -872,7 +872,8 @@ set_rcvbuf:
 
                if (val & SOF_TIMESTAMPING_OPT_ID &&
                    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
-                       if (sk->sk_protocol == IPPROTO_TCP) {
+                       if (sk->sk_protocol == IPPROTO_TCP &&
+                           sk->sk_type == SOCK_STREAM) {
                                if (sk->sk_state != TCP_ESTABLISHED) {
                                        ret = -EINVAL;
                                        break;