kernel/linux.git/drivers/vhost/vhost.c, branch v4.14.286

vhost: Fix the calculation in vhost_overflow()

2021-08-26T12:37:08+00:00

[ Upstream commit f7ad318ea0ad58ebe0e595e59aed270bb643b29b ] This fixes the incorrect calculation for integer overflow when the last address of iova range is 0xffffffff. Fixes: ec33d031a14b ("vhost: detect 32 bit integer wrap around") Reported-by: Jason Wang Signed-off-by: Xie Yongji Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210728130756.97-2-xieyongji@bytedance.com Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin

vhost: Fix vhost_vq_reset()

2021-04-07T10:47:01+00:00

[ Upstream commit beb691e69f4dec7bfe8b81b509848acfd1f0dbf9 ] vhost_reset_is_le() is vhost_init_is_le(), and in the case of cross-endian legacy, vhost_init_is_le() depends on vq->user_be. vq->user_be is set by vhost_disable_cross_endian(). But in vhost_vq_reset(), we have: vhost_reset_is_le(vq); vhost_disable_cross_endian(vq); And so user_be is used before being set. To fix that, reverse the lines order as there is no other dependency between them. Signed-off-by: Laurent Vivier Link: https://lore.kernel.org/r/20210312140913.788592-1-lvivier@redhat.com Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin

vhost: make sure log_num < in_num

2019-09-16T06:20:46+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: introduce vhost_exceeds_weight()

2019-07-10T07:54:42+00:00

commit e82b9b0727ff6d665fff2d326162b460dded554d upstream. 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 Signed-off-by: Balbir Singh Signed-off-by: Greg Kroah-Hartman

vhost: reject zero size iova range

2019-04-27T07:35:34+00:00

[ Upstream commit 813dbeb656d6c90266f251d8bd2b02d445afa63f ] We used to accept zero size iova range which will lead a infinite loop in translate_desc(). Fixing this by failing the request in this case. Reported-by: syzbot+d21e6e297322a900c128@syzkaller.appspotmail.com Fixes: 6b1e6cc7 ("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: correctly check the return value of translate_desc() in log_used()

2019-02-23T08:06:43+00:00

[ Upstream commit 816db7663565cd23f74ed3d5c9240522e3fb0dda ] When fail, translate_desc() returns negative value, otherwise the number of iovs. So we should fail when the return value is negative instead of a blindly check against zero. Detected by CoverityScan, CID# 1442593: Control flow issues (DEADCODE) Fixes: cc5e71075947 ("vhost: log dirty page correctly") Acked-by: Michael S. Tsirkin Reported-by: Stephen Hemminger Signed-off-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: log dirty page correctly

2019-01-31T07:13:41+00:00

[ Upstream commit cc5e710759470bc7f3c61d11fd54586f15fdbdf4 ] Vhost dirty page logging API is designed to sync through GPA. But we try to log GIOVA when device IOTLB is enabled. This is wrong and may lead to missing data after migration. To solve this issue, when logging with device IOTLB enabled, we will: 1) reuse the device IOTLB translation result of GIOVA->HVA mapping to get HVA, for writable descriptor, get HVA through iovec. For used ring update, translate its GIOVA to HVA 2) traverse the GPA->HVA mapping to get the possible GPA and log through GPA. Pay attention this reverse mapping is not guaranteed to be unique, so we should log each possible GPA in this case. This fix the failure of scp to guest during migration. In -next, we will probably support passing GIOVA->GPA instead of GIOVA->HVA. Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API") Reported-by: Jintack Lim Cc: Jintack Lim Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: make sure used idx is seen before log in vhost_add_used_n()

2019-01-09T16:14:45+00:00

[ Upstream commit 841df922417eb82c835e93d4b93eb6a68c99d599 ] We miss a write barrier that guarantees used idx is updated and seen before log. This will let userspace sync and copy used ring before used idx is update. Fix this by adding a barrier before log_write(). Fixes: 8dd014adfea6f ("vhost-net: mergeable buffers support") Acked-by: Michael S. Tsirkin Signed-off-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: Fix Spectre V1 vulnerability

2018-11-04T13:52:49+00:00

[ Upstream commit ff002269a4ee9c769dbf9365acef633ebcbd6cbe ] The idx in vhost_vring_ioctl() was controlled by userspace, hence a potential exploitation of the Spectre variant 1 vulnerability. Fixing this by sanitizing idx before using it to index d->vqs. Cc: Michael S. Tsirkin Cc: Josh Poimboeuf Cc: Andrea Arcangeli Signed-off-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vhost: correctly check the iova range when waking virtqueue

2018-09-15T07:45:25+00:00

[ Upstream commit 2d66f997f0545c8f7fc5cf0b49af1decb35170e7 ] We don't wakeup the virtqueue if the first byte of pending iova range is the last byte of the range we just got updated. This will lead a virtqueue to wait for IOTLB updating forever. Fixing by correct the check and wake up the virtqueue in this case. Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API") Reported-by: Peter Xu Signed-off-by: Jason Wang Reviewed-by: Peter Xu Tested-by: Peter Xu Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman