[SRU Focal:oem-5.6 1/1] net/nfc/rawsock.c: add CAP_NET_RAW check.

[Thadeu Lima de Souza Cascardo]

From: Qingyu Li <ieatmuttonchuan at gmail.com>

When creating a raw AF_NFC socket, CAP_NET_RAW needs to be checked first.

Signed-off-by: Qingyu Li <ieatmuttonchuan at gmail.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit 26896f01467a28651f7a536143fe5ac8449d4041)
CVE-2020-26088
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo at canonical.com>
---
 net/nfc/rawsock.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index ba5ffd3badd3..b5c867fe3232 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -332,10 +332,13 @@ static int rawsock_create(struct net *net, struct socket *sock,
 	if ((sock->type != SOCK_SEQPACKET) && (sock->type != SOCK_RAW))
 		return -ESOCKTNOSUPPORT;
 
-	if (sock->type == SOCK_RAW)
+	if (sock->type == SOCK_RAW) {
+		if (!capable(CAP_NET_RAW))
+			return -EPERM;
 		sock->ops = &rawsock_raw_ops;
-	else
+	} else {
 		sock->ops = &rawsock_ops;
+	}
 
 	sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto, kern);
 	if (!sk)
-- 
2.25.1