yongduan ba03ee62ae vhost: make sure log_num < in_num ... commit 060423bfde 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: 3a4d5c94e9 ("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>		2019-09-16 08:22:25 +02:00
..
Kconfig	vhost: allow vhost-scsi driver to be built-in	2018-08-22 01:01:32 +03:00
Kconfig.vringh
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
net.c	vhost_net: fix possible infinite loop	2019-08-04 09:30:55 +02:00
scsi.c	vhost: scsi: add weight support	2019-08-04 09:30:55 +02:00
test.c	vhost/test: fix build for vhost test - again	2019-09-16 08:21:40 +02:00
test.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
vhost.c	vhost: make sure log_num < in_num	2019-09-16 08:22:25 +02:00
vhost.h	vhost: introduce vhost_exceeds_weight()	2019-08-04 09:30:55 +02:00
vringh.c	treewide: kmalloc() -> kmalloc_array()	2018-06-12 16:19:22 -07:00
vsock.c	vhost: vsock: add weight support	2019-08-04 09:30:55 +02:00