add patch for CVE-2018-1118
authorStoiko Ivanov <s.ivanov@proxmox.com>
Wed, 22 Aug 2018 09:48:05 +0000 (11:48 +0200)
committerThomas Lamprecht <t.lamprecht@proxmox.com>
Wed, 22 Aug 2018 11:01:23 +0000 (13:01 +0200)
The commit is already on bionic/master-next (first commit after the
latest tag on master-next)

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
patches/kernel/0014-vhost-fix-info-leak-due-to-uninitialized-memory.patch [new file with mode: 0644]

diff --git a/patches/kernel/0014-vhost-fix-info-leak-due-to-uninitialized-memory.patch b/patches/kernel/0014-vhost-fix-info-leak-due-to-uninitialized-memory.patch
new file mode 100644 (file)
index 0000000..a627235
--- /dev/null
@@ -0,0 +1,45 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: "Michael S. Tsirkin" <mst@redhat.com>
+Date: Thu, 16 Aug 2018 17:02:36 +0800
+Subject: [PATCH] vhost: fix info leak due to uninitialized memory
+
+CVE-2018-1118
+
+struct vhost_msg within struct vhost_msg_node is copied to userspace.
+Unfortunately it turns out on 64 bit systems vhost_msg has padding after
+type which gcc doesn't initialize, leaking 4 uninitialized bytes to
+userspace.
+
+This padding also unfortunately means 32 bit users of this interface are
+broken on a 64 bit kernel which will need to be fixed separately.
+
+Fixes: CVE-2018-1118
+Cc: stable@vger.kernel.org
+Reported-by: Kevin Easton <kevin@guarana.org>
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+Reported-by: syzbot+87cfa083e727a224754b@syzkaller.appspotmail.com
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+(cherry picked from commit 670ae9caaca467ea1bfd325cb2a5c98ba87f94ad)
+Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
+Acked-by: Khalid Elmously <khalid.elmously@canonical.com>
+Acked-by: Kamal Mostafa <kamal@canonical.com>
+Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
+Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
+---
+ drivers/vhost/vhost.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
+index 31bdfd296ced..a922d3d28a20 100644
+--- a/drivers/vhost/vhost.c
++++ b/drivers/vhost/vhost.c
+@@ -2383,6 +2383,9 @@ struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type)
+       struct vhost_msg_node *node = kmalloc(sizeof *node, GFP_KERNEL);
+       if (!node)
+               return NULL;
++
++      /* Make sure all padding within the structure is initialized. */
++      memset(&node->msg, 0, sizeof node->msg);
+       node->vq = vq;
+       node->msg.type = type;
+       return node;