| Message ID | 20240218-reuse-v5-2-e4fc1c19b5a9@daynix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | hw/pci: SR-IOV related fixes and improvements | expand |
On Sun, Feb 18, 2024 at 01:56:07PM +0900, Akihiko Odaki wrote: > The guest may write NumVFs greater than TotalVFs and that can lead > to buffer overflow in VF implementations. > > Cc: qemu-stable@nongnu.org > 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); This reminds me: how is this num_vfs value set on migration? > > -- > 2.43.1
On 2024/02/19 2:36, Michael S. Tsirkin wrote: > On Sun, Feb 18, 2024 at 01:56:07PM +0900, Akihiko Odaki wrote: >> The guest may write NumVFs greater than TotalVFs and that can lead >> to buffer overflow in VF implementations. >> >> Cc: qemu-stable@nongnu.org >> 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); > > > This reminds me: how is this num_vfs value set on migration? That's a good point... Actually no consideration of migration is made and SR-IOV is completely broken with it.
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);
The guest may write NumVFs greater than TotalVFs and that can lead to buffer overflow in VF implementations. Cc: qemu-stable@nongnu.org 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(+)