diff options
| author | Andrea Parri (Microsoft) <parri.andrea@gmail.com> | 2021-01-14 23:26:28 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-01-19 06:47:47 +0300 |
| commit | 505e3f00c3f3648cb6260deb35e87fae1f64f5d8 (patch) | |
| tree | 7dd0f2939b234775da7bc5973fc633ba6a6ae757 /drivers/net/hyperv/netvsc_drv.c | |
| parent | a98c0c47420412ef94d6f45f9ae607258929aa10 (diff) | |
| download | linux-505e3f00c3f3648cb6260deb35e87fae1f64f5d8.tar.xz | |
hv_netvsc: Add (more) validation for untrusted Hyper-V values
For additional robustness in the face of Hyper-V errors or malicious
behavior, validate all values that originate from packets that Hyper-V
has sent to the guest. Ensure that invalid values cannot cause indexing
off the end of an array, or subvert an existing validation via integer
overflow. Ensure that outgoing packets do not have any leftover guest
memory that has not been zeroed out.
Reported-by: Juan Vazquez <juvazq@microsoft.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/20210114202628.119541-1-parri.andrea@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/hyperv/netvsc_drv.c')
| -rw-r--r-- | drivers/net/hyperv/netvsc_drv.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 75b4d6703cf1..ac20c432d4d8 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -761,6 +761,16 @@ void netvsc_linkstatus_callback(struct net_device *net, if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) { u32 speed; + /* Validate status_buf_offset */ + if (indicate->status_buflen < sizeof(speed) || + indicate->status_buf_offset < sizeof(*indicate) || + resp->msg_len - RNDIS_HEADER_SIZE < indicate->status_buf_offset || + resp->msg_len - RNDIS_HEADER_SIZE - indicate->status_buf_offset + < indicate->status_buflen) { + netdev_err(net, "invalid rndis_indicate_status packet\n"); + return; + } + speed = *(u32 *)((void *)indicate + indicate->status_buf_offset) / 10000; ndev_ctx->speed = speed; @@ -866,8 +876,14 @@ static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net, */ if (csum_info && csum_info->receive.ip_checksum_value_invalid && csum_info->receive.ip_checksum_succeeded && - skb->protocol == htons(ETH_P_IP)) + skb->protocol == htons(ETH_P_IP)) { + /* Check that there is enough space to hold the IP header. */ + if (skb_headlen(skb) < sizeof(struct iphdr)) { + kfree_skb(skb); + return NULL; + } netvsc_comp_ipcsum(skb); + } /* Do L4 checksum offload if enabled and present. */ if (csum_info && (net->features & NETIF_F_RXCSUM)) { |