kernel/linux.git/drivers/vhost, branch v4.19.112

vhost: Check docket sk_family instead of call getname

2020-03-05T15:42:18+00:00

commit 42d84c8490f9f0931786f1623191fcab397c3d64 upstream. Doing so, we save one call to get data we already have in the struct. Also, since there is no guarantee that getname use sockaddr_ll parameter beyond its size, we add a little bit of security here. It should do not do beyond MAX_ADDR_LEN, but syzbot found that ax25_getname writes more (72 bytes, the size of full_sockaddr_ax25, versus 20 + 32 bytes of sockaddr_ll + MAX_ADDR_LEN in syzbot repro). Fixes: 3a4d5c94e9593 ("vhost_net: a kernel-level virtio server") Reported-by: syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com Signed-off-by: Eugenio Pérez Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost/test: stop device before reset

2020-01-27T13:51:19+00:00

[ Upstream commit 245cdd9fbd396483d501db83047116e2530f245f ] When device stop was moved out of reset, test device wasn't updated to stop before reset, this resulted in a use after free. Fix by invoking stop appropriately. Fixes: b211616d7125 ("vhost: move -net specific code out") Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin

vhost/vsock: accept only packets with the right dst_cid

2020-01-04T18:13:36+00:00

[ Upstream commit 8a3cc29c316c17de590e3ff8b59f3d6cbfd37b0a ] When we receive a new packet from the guest, we check if the src_cid is correct, but we forgot to check the dst_cid. The host should accept only packets where dst_cid is equal to the host CID. Signed-off-by: Stefano Garzarella Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost/vsock: split packets to send using multiple buffers

2019-12-01T08:16:08+00:00

commit 6dbd3e66e7785a2f055bf84d98de9b8fd31ff3f5 upstream. If the packets to sent to the guest are bigger than the buffer available, we can split them, using multiple buffers and fixing the length in the packet header. This is safe since virtio-vsock supports only stream sockets. Signed-off-by: Stefano Garzarella Reviewed-by: Stefan Hajnoczi Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: make sure log_num < in_num

2019-09-16T06:22:25+00:00

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 Signed-off-by: ruippan Signed-off-by: yongduan Acked-by: Michael S. Tsirkin Reviewed-by: Tyler Hicks Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

vhost/test: fix build for vhost test - again

2019-09-16T06:21:40+00:00

commit 264b563b8675771834419057cbe076c1a41fb666 upstream. Since vhost_exceeds_weight() was introduced, callers need to specify the packet weight and byte weight in vhost_dev_init(). Note that, the packet weight isn't counted in this patch to keep the original behavior unchanged. Fixes: e82b9b0727ff ("vhost: introduce vhost_exceeds_weight()") Cc: stable@vger.kernel.org Signed-off-by: Tiwei Bie Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Signed-off-by: Greg Kroah-Hartman

vhost/test: fix build for vhost test

2019-09-16T06:21:40+00:00

commit 93d2c4de8d8129b97ee1e1a222aedb0719d2fcd9 upstream. Since below commit, callers need to specify the iov_limit in vhost_dev_init() explicitly. Fixes: b46a0bf78ad7 ("vhost: fix OOB in get_rx_bufs()") Cc: stable@vger.kernel.org Signed-off-by: Tiwei Bie Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Signed-off-by: Greg Kroah-Hartman

vhost: scsi: add weight support

2019-08-04T07:30:55+00:00

commit c1ea02f15ab5efb3e93fc3144d895410bf79fcf2 upstream. This patch will check the weight and exit the loop if we exceeds the weight. This is useful for preventing scsi kthread from hogging cpu which is guest triggerable. This addresses CVE-2019-3900. Cc: Paolo Bonzini Cc: Stefan Hajnoczi Fixes: 057cbf49a1f0 ("tcm_vhost: Initial merge for vhost level target fabric driver") Signed-off-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin Reviewed-by: Stefan Hajnoczi [jwang: backport to 4.19] Signed-off-by: Jack Wang Signed-off-by: Greg Kroah-Hartman

vhost: vsock: add weight support

2019-08-04T07:30:55+00:00

commit e79b431fb901ba1106670bcc80b9b617b25def7d upstream. This patch will check the weight and exit the loop if we exceeds the weight. This is useful for preventing vsock kthread from hogging cpu which is guest triggerable. The weight can help to avoid starving the request from on direction while another direction is being processed. The value of weight is picked from vhost-net. This addresses CVE-2019-3900. Cc: Stefan Hajnoczi Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko") Signed-off-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

vhost_net: fix possible infinite loop

2019-08-04T07:30:55+00:00

commit e2412c07f8f3040593dfb88207865a3cd58680c0 upstream. When the rx buffer is too small for a packet, we will discard the vq descriptor and retry it for the next packet: while ((sock_len = vhost_net_rx_peek_head_len(net, sock->sk, &busyloop_intr))) { ... /* On overrun, truncate and discard */ if (unlikely(headcount > UIO_MAXIOV)) { iov_iter_init(&msg.msg_iter, READ, vq->iov, 1, 1); err = sock->ops->recvmsg(sock, &msg, 1, MSG_DONTWAIT | MSG_TRUNC); pr_debug("Discarded rx packet: len %zd\n", sock_len); continue; } ... } This makes it possible to trigger a infinite while..continue loop through the co-opreation of two VMs like: 1) Malicious VM1 allocate 1 byte rx buffer and try to slow down the vhost process as much as possible e.g using indirect descriptors or other. 2) Malicious VM2 generate packets to VM1 as fast as possible Fixing this by checking against weight at the end of RX and TX loop. This also eliminate other similar cases when: - userspace is consuming the packets in the meanwhile - theoretical TOCTOU attack if guest moving avail index back and forth to hit the continue after vhost find guest just add new buffers This addresses CVE-2019-3900. Fixes: d8316f3991d20 ("vhost: fix total length when packets are too short") Fixes: 3a4d5c94e9593 ("vhost_net: a kernel-level virtio server") Signed-off-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin [jwang: backport to 4.19] Signed-off-by: Jack Wang Signed-off-by: Greg Kroah-Hartman