dpdk/SOURCES/0002-vhost-fix-header-spann...

107 lines
3.5 KiB
Diff

From e12d415556994d0901c317f6338ed2961185465f Mon Sep 17 00:00:00 2001
Message-Id: <e12d415556994d0901c317f6338ed2961185465f.1666780268.git.tredaelli@redhat.com>
In-Reply-To: <f167022606b5ccca27a627ae599538ce2348ef67.1666780268.git.tredaelli@redhat.com>
References: <f167022606b5ccca27a627ae599538ce2348ef67.1666780268.git.tredaelli@redhat.com>
From: Maxime Coquelin <maxime.coquelin@redhat.com>
Date: Thu, 16 Jun 2022 14:25:07 +0200
Subject: [PATCH 2/2] vhost: fix header spanned across more than two
descriptors
[ upstream commit dc1516e260a0df272b218392faf6db3cbf45e717 ]
This patch aims at supporting the unlikely case where a
Virtio-net header is spanned across more than two
descriptors.
CVE-2022-2132
Fixes: fd68b4739d2c ("vhost: use buffer vectors in dequeue path")
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Chenbo Xia <chenbo.xia@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>
---
lib/vhost/virtio_net.c | 41 +++++++++++++----------------------------
1 file changed, 13 insertions(+), 28 deletions(-)
diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c
index 991a7a2bd4..bf4d75b4bd 100644
--- a/lib/vhost/virtio_net.c
+++ b/lib/vhost/virtio_net.c
@@ -2322,25 +2322,22 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq,
uint32_t buf_avail, buf_offset;
uint64_t buf_addr, buf_len;
uint32_t mbuf_avail, mbuf_offset;
+ uint32_t hdr_remain = dev->vhost_hlen;
uint32_t cpy_len;
struct rte_mbuf *cur = m, *prev = m;
struct virtio_net_hdr tmp_hdr;
struct virtio_net_hdr *hdr = NULL;
- /* A counter to avoid desc dead loop chain */
- uint16_t vec_idx = 0;
+ uint16_t vec_idx;
struct batch_copy_elem *batch_copy = vq->batch_copy_elems;
int error = 0;
- buf_addr = buf_vec[vec_idx].buf_addr;
- buf_len = buf_vec[vec_idx].buf_len;
-
/*
* The caller has checked the descriptors chain is larger than the
* header size.
*/
if (virtio_net_with_host_offload(dev)) {
- if (unlikely(buf_len < sizeof(struct virtio_net_hdr))) {
+ if (unlikely(buf_vec[0].buf_len < sizeof(struct virtio_net_hdr))) {
/*
* No luck, the virtio-net header doesn't fit
* in a contiguous virtual area.
@@ -2348,34 +2345,22 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq,
copy_vnet_hdr_from_desc(&tmp_hdr, buf_vec);
hdr = &tmp_hdr;
} else {
- hdr = (struct virtio_net_hdr *)((uintptr_t)buf_addr);
+ hdr = (struct virtio_net_hdr *)((uintptr_t)buf_vec[0].buf_addr);
}
}
- /*
- * A virtio driver normally uses at least 2 desc buffers
- * for Tx: the first for storing the header, and others
- * for storing the data.
- */
- if (unlikely(buf_len < dev->vhost_hlen)) {
- buf_offset = dev->vhost_hlen - buf_len;
- vec_idx++;
- buf_addr = buf_vec[vec_idx].buf_addr;
- buf_len = buf_vec[vec_idx].buf_len;
- buf_avail = buf_len - buf_offset;
- } else if (buf_len == dev->vhost_hlen) {
- if (unlikely(++vec_idx >= nr_vec))
- goto out;
- buf_addr = buf_vec[vec_idx].buf_addr;
- buf_len = buf_vec[vec_idx].buf_len;
+ for (vec_idx = 0; vec_idx < nr_vec; vec_idx++) {
+ if (buf_vec[vec_idx].buf_len > hdr_remain)
+ break;
- buf_offset = 0;
- buf_avail = buf_len;
- } else {
- buf_offset = dev->vhost_hlen;
- buf_avail = buf_vec[vec_idx].buf_len - dev->vhost_hlen;
+ hdr_remain -= buf_vec[vec_idx].buf_len;
}
+ buf_addr = buf_vec[vec_idx].buf_addr;
+ buf_len = buf_vec[vec_idx].buf_len;
+ buf_offset = hdr_remain;
+ buf_avail = buf_vec[vec_idx].buf_len - hdr_remain;
+
PRINT_PACKET(dev,
(uintptr_t)(buf_addr + buf_offset),
(uint32_t)buf_avail, 0);
--
2.37.3