| Message ID | 20180813222313.3510-1-jcline@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd() | expand |
From: Jeremy Cline <jcline@redhat.com> Date: Mon, 13 Aug 2018 22:23:13 +0000 > req->sdiag_family is a user-controlled value that's used as an array > index. Sanitize it after the bounds check to avoid speculative > out-of-bounds array access. > > This also protects the sock_is_registered() call, so this removes the > sanitize call there. > > Fixes: e978de7a6d38 ("net: socket: Fix potential spectre v1 gadget in sock_is_registered") > Cc: Josh Poimboeuf <jpoimboe@redhat.com> > Cc: konrad.wilk@oracle.com > Cc: jamie.iles@oracle.com > Cc: liran.alon@oracle.com > Cc: stable@vger.kernel.org > Signed-off-by: Jeremy Cline <jcline@redhat.com> > --- > > Since commit e978de7a6d38 didn't apply cleanly to v4.14, this won't > either since it reverts that change. To apply cleanly there, the change > to sock_is_registered() needs to be dropped. Applied, thank you.
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index c37b5be7c5e4..3312a5849a97 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -10,6 +10,7 @@ #include <linux/kernel.h> #include <linux/tcp.h> #include <linux/workqueue.h> +#include <linux/nospec.h> #include <linux/inet_diag.h> #include <linux/sock_diag.h> @@ -218,6 +219,7 @@ static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh) if (req->sdiag_family >= AF_MAX) return -EINVAL; + req->sdiag_family = array_index_nospec(req->sdiag_family, AF_MAX); if (sock_diag_handlers[req->sdiag_family] == NULL) sock_load_diag_module(req->sdiag_family, 0); diff --git a/net/socket.c b/net/socket.c index 53c907169818..391a0da49ffe 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2679,8 +2679,7 @@ EXPORT_SYMBOL(sock_unregister); bool sock_is_registered(int family) { - return family < NPROTO && - rcu_access_pointer(net_families[array_index_nospec(family, NPROTO)]); + return family < NPROTO && rcu_access_pointer(net_families[family]); } static int __init sock_init(void)
req->sdiag_family is a user-controlled value that's used as an array index. Sanitize it after the bounds check to avoid speculative out-of-bounds array access. This also protects the sock_is_registered() call, so this removes the sanitize call there. Fixes: e978de7a6d38 ("net: socket: Fix potential spectre v1 gadget in sock_is_registered") Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: konrad.wilk@oracle.com Cc: jamie.iles@oracle.com Cc: liran.alon@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Jeremy Cline <jcline@redhat.com> --- Since commit e978de7a6d38 didn't apply cleanly to v4.14, this won't either since it reverts that change. To apply cleanly there, the change to sock_is_registered() needs to be dropped. net/core/sock_diag.c | 2 ++ net/socket.c | 3 +-- 2 files changed, 3 insertions(+), 2 deletions(-)