From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50810 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730597AbeKLFs0 (ORCPT ); Mon, 12 Nov 2018 00:48:26 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Josh Poimboeuf" , "David S. Miller" , "Jeremy Cline" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: Subject: [PATCH 3.16 300/366] net: socket: fix potential spectre v1 gadget in socketcall In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jeremy Cline commit c8e8cd579bb4265651df8223730105341e61a2d1 upstream. 'call' is a user-controlled value, so sanitize the array index after the bounds check to avoid speculating past the bounds of the 'nargs' array. Found with the help of Smatch: net/socket.c:2508 __do_sys_socketcall() warn: potential spectre issue 'nargs' [r] (local cap) Cc: Josh Poimboeuf Signed-off-by: Jeremy Cline Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/socket.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/socket.c +++ b/net/socket.c @@ -89,6 +89,7 @@ #include #include #include +#include #include #include @@ -2494,6 +2495,7 @@ SYSCALL_DEFINE2(socketcall, int, call, u if (call < 1 || call > SYS_SENDMMSG) return -EINVAL; + call = array_index_nospec(call, SYS_SENDMMSG + 1); len = nargs[call]; if (len > sizeof(a))