From: Jeremy Cline <jcline@redhat.com>
Date: Fri, 27 Jul 2018 22:43:02 +0000 (+0000)
Subject: net: socket: Fix potential spectre v1 gadget in sock_is_registered
X-Git-Tag: v4.17.13~17
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=82d0d07a25ebdfebaa2aa3fe713ea6311f5b8669;p=thirdparty%2Fkernel%2Fstable.git

net: socket: Fix potential spectre v1 gadget in sock_is_registered

commit e978de7a6d382ec378830ca2cf38e902df0b6d84 upstream.

'family' can be a user-controlled value, so sanitize it after the bounds
check to avoid speculative out-of-bounds access.

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/socket.c b/net/socket.c
index 0316b380389e4..6a6aa84b64c17 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2694,7 +2694,8 @@ EXPORT_SYMBOL(sock_unregister);
 
 bool sock_is_registered(int family)
 {
-	return family < NPROTO && rcu_access_pointer(net_families[family]);
+	return family < NPROTO &&
+		rcu_access_pointer(net_families[array_index_nospec(family, NPROTO)]);
 }
 
 static int __init sock_init(void)