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authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-03 15:00:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-03 15:00:39 -0700
commit43e1b12927276cde8052122a24ff796649f09d60 (patch)
treee1629f35aca8b865691932bea03d51517926acb0 /drivers/char
parentd4ec3d5535c784c3adbc41c2bbc5d17a00a4a898 (diff)
parent540061ac79f0302ae91e44e6cd216cbaa3af1757 (diff)
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin: "vhost and virtio fixes and features: - Hardening work by Jason - vdpa driver for Alibaba ENI - Performance tweaks for virtio blk - virtio rng rework using an internal buffer - mac/mtu programming for mlx5 vdpa - Misc fixes, cleanups" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (45 commits) vdpa/mlx5: Forward only packets with allowed MAC address vdpa/mlx5: Support configuration of MAC vdpa/mlx5: Fix clearing of VIRTIO_NET_F_MAC feature bit vdpa_sim_net: Enable user to set mac address and mtu vdpa: Enable user to set mac and mtu of vdpa device vdpa: Use kernel coding style for structure comments vdpa: Introduce query of device config layout vdpa: Introduce and use vdpa device get, set config helpers virtio-scsi: don't let virtio core to validate used buffer length virtio-blk: don't let virtio core to validate used length virtio-net: don't let virtio core to validate used length virtio_ring: validate used buffer length virtio_blk: correct types for status handling virtio_blk: allow 0 as num_request_queues i2c: virtio: Add support for zero-length requests virtio-blk: fixup coccinelle warnings virtio_ring: fix typos in vring_desc_extra virtio-pci: harden INTX interrupts virtio_pci: harden MSI-X interrupts virtio_config: introduce a new .enable_cbs method ...
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/hw_random/virtio-rng.c86
-rw-r--r--drivers/char/virtio_console.c9
2 files changed, 74 insertions, 21 deletions
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index a90001e02bf7..0a7dde135db1 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -18,13 +18,20 @@ static DEFINE_IDA(rng_index_ida);
struct virtrng_info {
struct hwrng hwrng;
struct virtqueue *vq;
- struct completion have_data;
char name[25];
- unsigned int data_avail;
int index;
- bool busy;
bool hwrng_register_done;
bool hwrng_removed;
+ /* data transfer */
+ struct completion have_data;
+ unsigned int data_avail;
+ unsigned int data_idx;
+ /* minimal size returned by rng_buffer_size() */
+#if SMP_CACHE_BYTES < 32
+ u8 data[32];
+#else
+ u8 data[SMP_CACHE_BYTES];
+#endif
};
static void random_recv_done(struct virtqueue *vq)
@@ -35,54 +42,88 @@ static void random_recv_done(struct virtqueue *vq)
if (!virtqueue_get_buf(vi->vq, &vi->data_avail))
return;
+ vi->data_idx = 0;
+
complete(&vi->have_data);
}
-/* The host will fill any buffer we give it with sweet, sweet randomness. */
-static void register_buffer(struct virtrng_info *vi, u8 *buf, size_t size)
+static void request_entropy(struct virtrng_info *vi)
{
struct scatterlist sg;
- sg_init_one(&sg, buf, size);
+ reinit_completion(&vi->have_data);
+ vi->data_avail = 0;
+ vi->data_idx = 0;
+
+ sg_init_one(&sg, vi->data, sizeof(vi->data));
/* There should always be room for one buffer. */
- virtqueue_add_inbuf(vi->vq, &sg, 1, buf, GFP_KERNEL);
+ virtqueue_add_inbuf(vi->vq, &sg, 1, vi->data, GFP_KERNEL);
virtqueue_kick(vi->vq);
}
+static unsigned int copy_data(struct virtrng_info *vi, void *buf,
+ unsigned int size)
+{
+ size = min_t(unsigned int, size, vi->data_avail);
+ memcpy(buf, vi->data + vi->data_idx, size);
+ vi->data_idx += size;
+ vi->data_avail -= size;
+ if (vi->data_avail == 0)
+ request_entropy(vi);
+ return size;
+}
+
static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait)
{
int ret;
struct virtrng_info *vi = (struct virtrng_info *)rng->priv;
+ unsigned int chunk;
+ size_t read;
if (vi->hwrng_removed)
return -ENODEV;
- if (!vi->busy) {
- vi->busy = true;
- reinit_completion(&vi->have_data);
- register_buffer(vi, buf, size);
+ read = 0;
+
+ /* copy available data */
+ if (vi->data_avail) {
+ chunk = copy_data(vi, buf, size);
+ size -= chunk;
+ read += chunk;
}
if (!wait)
- return 0;
-
- ret = wait_for_completion_killable(&vi->have_data);
- if (ret < 0)
- return ret;
+ return read;
+
+ /* We have already copied available entropy,
+ * so either size is 0 or data_avail is 0
+ */
+ while (size != 0) {
+ /* data_avail is 0 but a request is pending */
+ ret = wait_for_completion_killable(&vi->have_data);
+ if (ret < 0)
+ return ret;
+ /* if vi->data_avail is 0, we have been interrupted
+ * by a cleanup, but buffer stays in the queue
+ */
+ if (vi->data_avail == 0)
+ return read;
- vi->busy = false;
+ chunk = copy_data(vi, buf + read, size);
+ size -= chunk;
+ read += chunk;
+ }
- return vi->data_avail;
+ return read;
}
static void virtio_cleanup(struct hwrng *rng)
{
struct virtrng_info *vi = (struct virtrng_info *)rng->priv;
- if (vi->busy)
- wait_for_completion(&vi->have_data);
+ complete(&vi->have_data);
}
static int probe_common(struct virtio_device *vdev)
@@ -118,6 +159,9 @@ static int probe_common(struct virtio_device *vdev)
goto err_find;
}
+ /* we always have a pending entropy request */
+ request_entropy(vi);
+
return 0;
err_find:
@@ -133,9 +177,9 @@ static void remove_common(struct virtio_device *vdev)
vi->hwrng_removed = true;
vi->data_avail = 0;
+ vi->data_idx = 0;
complete(&vi->have_data);
vdev->config->reset(vdev);
- vi->busy = false;
if (vi->hwrng_register_done)
hwrng_unregister(&vi->hwrng);
vdev->config->del_vqs(vdev);
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 7eaf303a7a86..660c5c388c29 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -28,6 +28,7 @@
#include "../tty/hvc/hvc_console.h"
#define is_rproc_enabled IS_ENABLED(CONFIG_REMOTEPROC)
+#define VIRTCONS_MAX_PORTS 0x8000
/*
* This is a global struct for storing common data for all the devices
@@ -2036,6 +2037,14 @@ static int virtcons_probe(struct virtio_device *vdev)
virtio_cread_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
struct virtio_console_config, max_nr_ports,
&portdev->max_nr_ports) == 0) {
+ if (portdev->max_nr_ports == 0 ||
+ portdev->max_nr_ports > VIRTCONS_MAX_PORTS) {
+ dev_err(&vdev->dev,
+ "Invalidate max_nr_ports %d",
+ portdev->max_nr_ports);
+ err = -EINVAL;
+ goto free;
+ }
multiport = true;
}