5.2-stable patches

added patches:
	vhost-block-speculation-of-translated-descriptors.patch
	vhost-make-sure-log_num-in_num.patch

diff --git a/queue-5.2/series b/queue-5.2/series
index e207eefa9b454d1795749f7754d67fdf7d6357e7..3ca110cdfc89c337863905650d63768bb3bb5344 100644 (file)
--- a/queue-5.2/series
+++ b/queue-5.2/series
@@ -33,3 +33,5 @@ drm-i915-whitelist-ps_-depth-invocation-_count.patch
 drm-i915-add-whitelist-workarounds-for-icl.patch
 drm-i915-icl-whitelist-ps_-depth-invocation-_count.patch
 btrfs-fix-unwritten-extent-buffers-and-hangs-on-future-writeback-attempts.patch
+vhost-block-speculation-of-translated-descriptors.patch
+vhost-make-sure-log_num-in_num.patch

diff --git a/queue-5.2/vhost-block-speculation-of-translated-descriptors.patch b/queue-5.2/vhost-block-speculation-of-translated-descriptors.patch
new file mode 100644 (file)
index 0000000..098ddca
--- /dev/null
+++ b/queue-5.2/vhost-block-speculation-of-translated-descriptors.patch
@@ -0,0 +1,46 @@
+From a89db445fbd7f1f8457b03759aa7343fa530ef6b Mon Sep 17 00:00:00 2001
+From: "Michael S. Tsirkin" <mst@redhat.com>
+Date: Sun, 8 Sep 2019 07:04:08 -0400
+Subject: vhost: block speculation of translated descriptors
+
+From: Michael S. Tsirkin <mst@redhat.com>
+
+commit a89db445fbd7f1f8457b03759aa7343fa530ef6b upstream.
+
+iovec addresses coming from vhost are assumed to be
+pre-validated, but in fact can be speculated to a value
+out of range.
+
+Userspace address are later validated with array_index_nospec so we can
+be sure kernel info does not leak through these addresses, but vhost
+must also not leak userspace info outside the allowed memory table to
+guests.
+
+Following the defence in depth principle, make sure
+the address is not validated out of node range.
+
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+Cc: stable@vger.kernel.org
+Acked-by: Jason Wang <jasowang@redhat.com>
+Tested-by: Jason Wang <jasowang@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/vhost/vhost.c |    6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/vhost/vhost.c
++++ b/drivers/vhost/vhost.c
+@@ -1965,8 +1965,10 @@ static int translate_desc(struct vhost_v
+               _iov = iov + ret;
+               size = node->size - addr + node->start;
+               _iov->iov_len = min((u64)len - s, size);
+-              _iov->iov_base = (void __user *)(unsigned long)
+-                      (node->userspace_addr + addr - node->start);
++              _iov->iov_base = (void __user *)
++                      ((unsigned long)node->userspace_addr +
++                       array_index_nospec((unsigned long)(addr - node->start),
++                                          node->size));
+               s += size;
+               addr += size;
+               ++ret;

diff --git a/queue-5.2/vhost-make-sure-log_num-in_num.patch b/queue-5.2/vhost-make-sure-log_num-in_num.patch
new file mode 100644 (file)
index 0000000..aaa4fc0
--- /dev/null
+++ b/queue-5.2/vhost-make-sure-log_num-in_num.patch
@@ -0,0 +1,54 @@
+From 060423bfdee3f8bc6e2c1bac97de24d5415e2bc4 Mon Sep 17 00:00:00 2001
+From: yongduan <yongduan@tencent.com>
+Date: Wed, 11 Sep 2019 17:44:24 +0800
+Subject: vhost: make sure log_num < in_num
+
+From: yongduan <yongduan@tencent.com>
+
+commit 060423bfdee3f8bc6e2c1bac97de24d5415e2bc4 upstream.
+
+The code assumes log_num < in_num everywhere, and that is true as long as
+in_num is incremented by descriptor iov count, and log_num by 1. However
+this breaks if there's a zero sized descriptor.
+
+As a result, if a malicious guest creates a vring desc with desc.len = 0,
+it may cause the host kernel to crash by overflowing the log array. This
+bug can be triggered during the VM migration.
+
+There's no need to log when desc.len = 0, so just don't increment log_num
+in this case.
+
+Fixes: 3a4d5c94e959 ("vhost_net: a kernel-level virtio server")
+Cc: stable@vger.kernel.org
+Reviewed-by: Lidong Chen <lidongchen@tencent.com>
+Signed-off-by: ruippan <ruippan@tencent.com>
+Signed-off-by: yongduan <yongduan@tencent.com>
+Acked-by: Michael S. Tsirkin <mst@redhat.com>
+Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/vhost/vhost.c |    4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/vhost/vhost.c
++++ b/drivers/vhost/vhost.c
+@@ -2074,7 +2074,7 @@ static int get_indirect(struct vhost_vir
+               /* If this is an input descriptor, increment that count. */
+               if (access == VHOST_ACCESS_WO) {
+                       *in_num += ret;
+-                      if (unlikely(log)) {
++                      if (unlikely(log && ret)) {
+                               log[*log_num].addr = vhost64_to_cpu(vq, desc.addr);
+                               log[*log_num].len = vhost32_to_cpu(vq, desc.len);
+                               ++*log_num;
+@@ -2217,7 +2217,7 @@ int vhost_get_vq_desc(struct vhost_virtq
+                       /* If this is an input descriptor,
+                        * increment that count. */
+                       *in_num += ret;
+-                      if (unlikely(log)) {
++                      if (unlikely(log && ret)) {
+                               log[*log_num].addr = vhost64_to_cpu(vq, desc.addr);
+                               log[*log_num].len = vhost32_to_cpu(vq, desc.len);
+                               ++*log_num;