kernel/linux.git/drivers/vhost/vsock.c, branch v5.2.16

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482

2019-06-19T15:09:52+00:00

Based on 1 normalized pattern(s): this work is licensed under the terms of the gnu gpl version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 48 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Enrico Weigelt Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081204.624030236@linutronix.de Signed-off-by: Greg Kroah-Hartman

vhost: vsock: add weight support

2019-05-27T15:08:23+00:00

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

vhost: introduce vhost_exceeds_weight()

2019-05-27T15:08:22+00:00

We used to have vhost_exceeds_weight() for vhost-net to: - prevent vhost kthread from hogging the cpu - balance the time spent between TX and RX This function could be useful for vsock and scsi as well. So move it to vhost.c. Device must specify a weight which counts the number of requests, or it can also specific a byte_weight which counts the number of bytes that has been processed. Signed-off-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin

vhost: fix OOB in get_rx_bufs()

2019-01-29T06:53:09+00:00

After batched used ring updating was introduced in commit e2b3b35eb989 ("vhost_net: batch used ring update in rx"). We tend to batch heads in vq->heads for more than one packet. But the quota passed to get_rx_bufs() was not correctly limited, which can result a OOB write in vq->heads. headcount = get_rx_bufs(vq, vq->heads + nvq->done_idx, vhost_len, &in, vq_log, &log, likely(mergeable) ? UIO_MAXIOV : 1); UIO_MAXIOV was still used which is wrong since we could have batched used in vq->heads, this will cause OOB if the next buffer needs more than 960 (1024 (UIO_MAXIOV) - 64 (VHOST_NET_BATCH)) heads after we've batched 64 (VHOST_NET_BATCH) heads: Acked-by: Stefan Hajnoczi ============================================================================= BUG kmalloc-8k (Tainted: G B ): Redzone overwritten ----------------------------------------------------------------------------- INFO: 0x00000000fd93b7a2-0x00000000f0713384. First byte 0xa9 instead of 0xcc INFO: Allocated in alloc_pd+0x22/0x60 age=3933677 cpu=2 pid=2674 kmem_cache_alloc_trace+0xbb/0x140 alloc_pd+0x22/0x60 gen8_ppgtt_create+0x11d/0x5f0 i915_ppgtt_create+0x16/0x80 i915_gem_create_context+0x248/0x390 i915_gem_context_create_ioctl+0x4b/0xe0 drm_ioctl_kernel+0xa5/0xf0 drm_ioctl+0x2ed/0x3a0 do_vfs_ioctl+0x9f/0x620 ksys_ioctl+0x6b/0x80 __x64_sys_ioctl+0x11/0x20 do_syscall_64+0x43/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 INFO: Slab 0x00000000d13e87af objects=3 used=3 fp=0x (null) flags=0x200000000010201 INFO: Object 0x0000000003278802 @offset=17064 fp=0x00000000e2e6652b Fixing this by allocating UIO_MAXIOV + VHOST_NET_BATCH iovs for vhost-net. This is done through set the limitation through vhost_dev_init(), then set_owner can allocate the number of iov in a per device manner. This fixes CVE-2018-16880. Fixes: e2b3b35eb989 ("vhost_net: batch used ring update in rx") Signed-off-by: Jason Wang Signed-off-by: David S. Miller

vhost/vsock: fix vhost vsock cid hashing inconsistent

2019-01-12T01:48:11+00:00

The vsock core only supports 32bit CID, but the Virtio-vsock spec define CID (dst_cid and src_cid) as u64 and the upper 32bits is reserved as zero. This inconsistency causes one bug in vhost vsock driver. The scenarios is: 0. A hash table (vhost_vsock_hash) is used to map an CID to a vsock object. And hash_min() is used to compute the hash key. hash_min() is defined as: (sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits)). That means the hash algorithm has dependency on the size of macro argument 'val'. 0. In function vhost_vsock_set_cid(), a 64bit CID is passed to hash_min() to compute the hash key when inserting a vsock object into the hash table. 0. In function vhost_vsock_get(), a 32bit CID is passed to hash_min() to compute the hash key when looking up a vsock for an CID. Because the different size of the CID, hash_min() returns different hash key, thus fails to look up the vsock object for an CID. To fix this bug, we keep CID as u64 in the IOCTLs and virtio message headers, but explicitly convert u64 to u32 when deal with the hash table and vsock core. Fixes: 834e772c8db0 ("vhost/vsock: fix use-after-free in network stack callers") Link: https://github.com/stefanha/virtio/blob/vsock/trunk/content.tex Signed-off-by: Zha Bin Reviewed-by: Liu Jiang Reviewed-by: Stefan Hajnoczi Acked-by: Jason Wang Signed-off-by: David S. Miller

vhost/vsock: switch to a mutex for vhost_vsock_hash

2018-12-19T23:23:49+00:00

Now that there are no more data path users of vhost_vsock_lock, it can be turned into a mutex. It's only used by .release() and in the .ioctl() path. Depends-on: <20181105103547.22018-1-stefanha@redhat.com> Suggested-by: Jason Wang Signed-off-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang

vhost/vsock: fix use-after-free in network stack callers

2018-12-06T19:28:38+00:00

If the network stack calls .send_pkt()/.cancel_pkt() during .release(), a struct vhost_vsock use-after-free is possible. This occurs because .release() does not wait for other CPUs to stop using struct vhost_vsock. Switch to an RCU-enabled hashtable (indexed by guest CID) so that .release() can wait for other CPUs by calling synchronize_rcu(). This also eliminates vhost_vsock_lock acquisition in the data path so it could have a positive effect on performance. This is CVE-2018-14625 "kernel: use-after-free Read in vhost_transport_send_pkt". Cc: stable@vger.kernel.org Reported-and-tested-by: syzbot+bd391451452fb0b93039@syzkaller.appspotmail.com Reported-by: syzbot+e3e074963495f92a89ed@syzkaller.appspotmail.com Reported-by: syzbot+d5a0a170c5069658b141@syzkaller.appspotmail.com Signed-off-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang

vhost/vsock: fix reset orphans race with close timeout

2018-12-06T19:22:34+00:00

If a local process has closed a connected socket and hasn't received a RST packet yet, then the socket remains in the table until a timeout expires. When a vhost_vsock instance is released with the timeout still pending, the socket is never freed because vhost_vsock has already set the SOCK_DONE flag. Check if the close timer is pending and let it close the socket. This prevents the race which can leak sockets. Reported-by: Maximilian Riemensberger Cc: Graham Whaley Signed-off-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2018-04-07T02:21:41+00:00

Pull fw_cfg, vhost updates from Michael Tsirkin: "This cleans up the qemu fw cfg device driver. On top of this, vmcore is dumped there on crash to help debugging with kASLR enabled. Also included are some fixes in vhost" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost: add vsock compat ioctl vhost: fix vhost ioctl signature to build with clang fw_cfg: write vmcoreinfo details crash: export paddr_vmcoreinfo_note() fw_cfg: add DMA register fw_cfg: add a public uapi header fw_cfg: handle fw_cfg_read_blob() error fw_cfg: remove inline from fw_cfg_read_blob() fw_cfg: fix sparse warnings around FW_CFG_FILE_DIR read fw_cfg: fix sparse warning reading FW_CFG_ID fw_cfg: fix sparse warnings with fw_cfg_file fw_cfg: fix sparse warnings in fw_cfg_sel_endianness() ptr_ring: fix build

vhost: add vsock compat ioctl

2018-03-20T01:17:42+00:00

This will allow usage of vsock from 32-bit binaries on a 64-bit kernel. Signed-off-by: Sonny Rao Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin