CVE-2015-8543 ipv6: DoS via NULL pointer dereference (rhbz 1290475 1290477)

kernel.spec

@@ -604,6 +604,9 @@ Patch572: alua_fix.patch
 #CVE-2015-7550 rhbz 1291197 1291198
 Patch575: KEYS-Fix-race-between-read-and-revoke.patch
 
+#CVE-2015-8543 rhbz 1290475 1290477
+Patch576: net-add-validation-for-the-socket-syscall-protocol-a.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -2047,6 +2050,9 @@ fi
 #
 # 
 %changelog
+* Tue Dec 15 2015 Josh Boyer <jwboyer@fedoraproject.org>
+- CVE-2015-8543 ipv6: DoS via NULL pointer dereference (rhbz 1290475 1290477)
+
 * Mon Dec 14 2015 Laura Abbott <labbott@redhat.com> - 4.4.0-0.rc5.git0.1
 - Linux v4.4-rc5
 - Disable debugging options.

net-add-validation-for-the-socket-syscall-protocol-a.patch

@@ -0,0 +1,139 @@
+From 4da7dc22c91ad2c3144cb1d0d96e9611bc86da47 Mon Sep 17 00:00:00 2001
+From: Hannes Frederic Sowa <hannes@stressinduktion.org>
+Date: Mon, 14 Dec 2015 22:03:39 +0100
+Subject: [PATCH] net: add validation for the socket syscall protocol argument
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+郭永刚 reported that one could simply crash the kernel as root by
+using a simple program:
+
+	int socket_fd;
+	struct sockaddr_in addr;
+	addr.sin_port = 0;
+	addr.sin_addr.s_addr = INADDR_ANY;
+	addr.sin_family = 10;
+
+	socket_fd = socket(10,3,0x40000000);
+	connect(socket_fd , &addr,16);
+
+AF_INET, AF_INET6 sockets actually only support 8-bit protocol
+identifiers. inet_sock's skc_protocol field thus is sized accordingly,
+thus larger protocol identifiers simply cut off the higher bits and
+store a zero in the protocol fields.
+
+This could lead to e.g. NULL function pointer because as a result of
+the cut off inet_num is zero and we call down to inet_autobind, which
+is NULL for raw sockets.
+
+kernel: Call Trace:
+kernel:  [<ffffffff816db90e>] ? inet_autobind+0x2e/0x70
+kernel:  [<ffffffff816db9a4>] inet_dgram_connect+0x54/0x80
+kernel:  [<ffffffff81645069>] SYSC_connect+0xd9/0x110
+kernel:  [<ffffffff810ac51b>] ? ptrace_notify+0x5b/0x80
+kernel:  [<ffffffff810236d8>] ? syscall_trace_enter_phase2+0x108/0x200
+kernel:  [<ffffffff81645e0e>] SyS_connect+0xe/0x10
+kernel:  [<ffffffff81779515>] tracesys_phase2+0x84/0x89
+
+I found no particular commit which introduced this problem.
+
+CVE: CVE-2015-8543
+Cc: Cong Wang <cwang@twopensource.com>
+Reported-by: 郭永刚 <guoyonggang@360.cn>
+Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ include/net/sock.h     | 1 +
+ net/ax25/af_ax25.c     | 3 +++
+ net/decnet/af_decnet.c | 3 +++
+ net/ipv4/af_inet.c     | 3 +++
+ net/ipv6/af_inet6.c    | 3 +++
+ net/irda/af_irda.c     | 3 +++
+ 6 files changed, 16 insertions(+)
+
+diff --git a/include/net/sock.h b/include/net/sock.h
+index 52d27ee924f4..2fa1fc00e8cb 100644
+--- a/include/net/sock.h
++++ b/include/net/sock.h
+@@ -403,6 +403,7 @@ struct sock {
+ 				sk_no_check_rx : 1,
+ 				sk_userlocks : 4,
+ 				sk_protocol  : 8,
++#define SK_PROTOCOL_MAX U8_MAX
+ 				sk_type      : 16;
+ 	kmemcheck_bitfield_end(flags);
+ 	int			sk_wmem_queued;
+diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
+index ae3a47f9d1d5..fbd0acf80b13 100644
+--- a/net/ax25/af_ax25.c
++++ b/net/ax25/af_ax25.c
+@@ -805,6 +805,9 @@ static int ax25_create(struct net *net, struct socket *sock, int protocol,
+ 	struct sock *sk;
+ 	ax25_cb *ax25;
+ 
++	if (protocol < 0 || protocol > SK_PROTOCOL_MAX)
++		return -EINVAL;
++
+ 	if (!net_eq(net, &init_net))
+ 		return -EAFNOSUPPORT;
+ 
+diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
+index eebf5ac8ce18..13d6b1a6e0fc 100644
+--- a/net/decnet/af_decnet.c
++++ b/net/decnet/af_decnet.c
+@@ -678,6 +678,9 @@ static int dn_create(struct net *net, struct socket *sock, int protocol,
+ {
+ 	struct sock *sk;
+ 
++	if (protocol < 0 || protocol > SK_PROTOCOL_MAX)
++		return -EINVAL;
++
+ 	if (!net_eq(net, &init_net))
+ 		return -EAFNOSUPPORT;
+ 
+diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
+index 11c4ca13ec3b..5c5db6636704 100644
+--- a/net/ipv4/af_inet.c
++++ b/net/ipv4/af_inet.c
+@@ -257,6 +257,9 @@ static int inet_create(struct net *net, struct socket *sock, int protocol,
+ 	int try_loading_module = 0;
+ 	int err;
+ 
++	if (protocol < 0 || protocol >= IPPROTO_MAX)
++		return -EINVAL;
++
+ 	sock->state = SS_UNCONNECTED;
+ 
+ 	/* Look for the requested type/protocol pair. */
+diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
+index 8ec0df75f1c4..9f5137cd604e 100644
+--- a/net/ipv6/af_inet6.c
++++ b/net/ipv6/af_inet6.c
+@@ -109,6 +109,9 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol,
+ 	int try_loading_module = 0;
+ 	int err;
+ 
++	if (protocol < 0 || protocol >= IPPROTO_MAX)
++		return -EINVAL;
++
+ 	/* Look for the requested type/protocol pair. */
+ lookup_protocol:
+ 	err = -ESOCKTNOSUPPORT;
+diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c
+index e6aa48b5395c..923abd6b3064 100644
+--- a/net/irda/af_irda.c
++++ b/net/irda/af_irda.c
+@@ -1086,6 +1086,9 @@ static int irda_create(struct net *net, struct socket *sock, int protocol,
+ 	struct sock *sk;
+ 	struct irda_sock *self;
+ 
++	if (protocol < 0 || protocol > SK_PROTOCOL_MAX)
++		return -EINVAL;
++
+ 	if (net != &init_net)
+ 		return -EAFNOSUPPORT;
+ 
+-- 
+2.5.0
+