RE: [PATCH v8 02/15] pcie_sriov: Validate NumVFs

[Sriram Yagnaraman]

> -----Original Message-----
> From: Akihiko Odaki <akihiko.odaki@daynix.com>
> Sent: Wednesday, 28 February 2024 12:33
> To: Philippe Mathieu-Daudé <philmd@linaro.org>; Michael S. Tsirkin
> <mst@redhat.com>; Marcel Apfelbaum <marcel.apfelbaum@gmail.com>;
> Alex Williamson <alex.williamson@redhat.com>; Cédric Le Goater
> <clg@redhat.com>; Paolo Bonzini <pbonzini@redhat.com>; Daniel P.
> Berrangé <berrange@redhat.com>; Eduardo Habkost
> <eduardo@habkost.net>; Sriram Yagnaraman
> <sriram.yagnaraman@ericsson.com>; Jason Wang <jasowang@redhat.com>;
> Keith Busch <kbusch@kernel.org>; Klaus Jensen <its@irrelevant.dk>; Markus
> Armbruster <armbru@redhat.com>
> Cc: qemu-devel@nongnu.org; qemu-block@nongnu.org; Akihiko Odaki
> <akihiko.odaki@daynix.com>; qemu-stable@nongnu.org
> Subject: [PATCH v8 02/15] pcie_sriov: Validate NumVFs
> 
> The guest may write NumVFs greater than TotalVFs and that can lead to buffer
> overflow in VF implementations.
> 
> Cc: qemu-stable@nongnu.org
> Fixes: CVE-2024-26327
> Fixes: 7c0fa8dff811 ("pcie: Add support for Single Root I/O Virtualization
> (SR/IOV)")
> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
> ---
>  hw/pci/pcie_sriov.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/hw/pci/pcie_sriov.c b/hw/pci/pcie_sriov.c index
> a1fe65f5d801..da209b7f47fd 100644
> --- a/hw/pci/pcie_sriov.c
> +++ b/hw/pci/pcie_sriov.c
> @@ -176,6 +176,9 @@ static void register_vfs(PCIDevice *dev)
> 
>      assert(sriov_cap > 0);
>      num_vfs = pci_get_word(dev->config + sriov_cap + PCI_SRIOV_NUM_VF);
> +    if (num_vfs > pci_get_word(dev->config + sriov_cap +
> PCI_SRIOV_TOTAL_VF)) {
> +        return;
> +    }
> 
>      dev->exp.sriov_pf.vf = g_new(PCIDevice *, num_vfs);
> 
> 
> --
> 2.43.2

Assuming change of my mail address from sriram.yagnaraman@est.tech to 
@ericsson.com is accepted,
Reviewed-by: Sriram Yagnaraman <sriram.yagnaraman@ericsson.com>