kernel/drivers/vhost/vhost.c, branch linux-4.16.y

vhost: fix info leak due to uninitialized memory

2018-06-25T23:54:06Z

commit 670ae9caaca467ea1bfd325cb2a5c98ba87f94ad upstream. 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 Signed-off-by: Michael S. Tsirkin Reported-by: syzbot+87cfa083e727a224754b@syzkaller.appspotmail.com Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

vhost: synchronize IOTLB message with dev cleanup

2018-06-11T20:48:17Z

[ Upstream commit 1b15ad683ab42a203f98b67045b40720e99d0e9a ] DaeRyong Jeong reports a race between vhost_dev_cleanup() and vhost_process_iotlb_msg(): Thread interleaving: CPU0 (vhost_process_iotlb_msg) CPU1 (vhost_dev_cleanup) (In the case of both VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE) ===== ===== vhost_umem_clean(dev->iotlb); if (!dev->iotlb) { ret = -EFAULT; break; } dev->iotlb = NULL; The reason is we don't synchronize between them, fixing by protecting vhost_process_iotlb_msg() with dev mutex. Reported-by: DaeRyong Jeong Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API") Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: Fix vhost_copy_to_user()

2018-04-19T06:54:05Z

[ Upstream commit 7ced6c98c7ab7a1f6743931e28671b833af79b1e ] vhost_copy_to_user is used to copy vring used elements to userspace. We should use VHOST_ADDR_USED instead of VHOST_ADDR_DESC. Fixes: f88949138058 ("vhost: introduce O(1) vq metadata cache") Signed-off-by: Eric Auger Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: fix vhost_vq_access_ok() log check

2018-04-19T06:54:04Z

[ Upstream commit d14d2b78090c7de0557362b26a4ca591aa6a9faa ] Commit d65026c6c62e7d9616c8ceb5a53b68bcdc050525 ("vhost: validate log when IOTLB is enabled") introduced a regression. The logic was originally: if (vq->iotlb) return 1; return A && B; After the patch the short-circuit logic for A was inverted: if (A || vq->iotlb) return A; return B; This patch fixes the regression by rewriting the checks in the obvious way, no longer returning A when vq->iotlb is non-NULL (which is hard to understand). Reported-by: syzbot+65a84dde0214b0387ccd@syzkaller.appspotmail.com Cc: Jason Wang Signed-off-by: Stefan Hajnoczi Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: validate log when IOTLB is enabled

2018-03-29T20:22:47Z

Vq log_base is the userspace address of bitmap which has nothing to do with IOTLB. So it needs to be validated unconditionally otherwise we may try use 0 as log_base which may lead to pin pages that will lead unexpected result (e.g trigger BUG_ON() in set_bit_to_user()). Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API") Reported-by: syzbot+6304bf97ef436580fede@syzkaller.appspotmail.com Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller

vhost: correctly remove wait queue during poll failure

2018-03-27T17:03:18Z

We tried to remove vq poll from wait queue, but do not check whether or not it was in a list before. This will lead double free. Fixing this by switching to use vhost_poll_stop() which zeros poll->wqh after removing poll from waitqueue to make sure it won't be freed twice. Cc: Darren Kenny Reported-by: syzbot+c0272972b01b872e604a@syzkaller.appspotmail.com Fixes: 2b8b328b61c79 ("vhost_net: handle polling errors when setting backend") Signed-off-by: Jason Wang Reviewed-by: Darren Kenny Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller

vfs: do bulk POLL* -> EPOLL* replacement

2018-02-11T22:34:03Z

This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^$[^\"]*$$\$/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro Signed-off-by: Linus Torvalds

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

2018-02-08T18:41:00Z

Pull virtio/vhost updates from Michael Tsirkin: "virtio, vhost: fixes, cleanups, features This includes the disk/cache memory stats for for the virtio balloon, as well as multiple fixes and cleanups" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost: don't hold onto file pointer for VHOST_SET_LOG_FD vhost: don't hold onto file pointer for VHOST_SET_VRING_ERR vhost: don't hold onto file pointer for VHOST_SET_VRING_CALL ringtest: ring.c malloc & memset to calloc virtio_vop: don't kfree device on register failure virtio_pci: don't kfree device on register failure virtio: split device_register into device_initialize and device_add vhost: remove unused lock check flag in vhost_dev_cleanup() vhost: Remove the unused variable. virtio_blk: print capacity at probe time virtio: make VIRTIO a menuconfig to ease disabling it all virtio/ringtest: virtio_ring: fix up need_event math virtio/ringtest: fix up need_event math virtio: virtio_mmio: make of_device_ids const. firmware: Use PTR_ERR_OR_ZERO() virtio-mmio: Use PTR_ERR_OR_ZERO() vhost/scsi: Improve a size determination in four functions virtio_balloon: include disk/file caches memory statistics

vhost: don't hold onto file pointer for VHOST_SET_LOG_FD

2018-02-01T14:26:47Z

We already hold a reference to the eventfd_ctx, which is sufficient; there's no need to hold a reference to the struct file as well. So get rid of vhost_dev->log_file. Signed-off-by: Eric Biggers Signed-off-by: Michael S. Tsirkin Reviewed-by: Jason Wang

vhost: don't hold onto file pointer for VHOST_SET_VRING_ERR

2018-02-01T14:26:47Z

We already hold a reference to the eventfd_ctx, which is sufficient; there's no need to hold a reference to the struct file as well. So get rid of vhost_virtqueue->error. Signed-off-by: Eric Biggers Signed-off-by: Michael S. Tsirkin Reviewed-by: Jason Wang