From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
This breaks uABI as the current code doesn't check padding and sev_fd
when unused.
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
Changes v3 -> v4:
- newly added
---
arch/x86/kvm/x86.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ab36e8940f1b..1d6085af6a00 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7055,6 +7055,22 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
r = -EFAULT;
goto out;
}
+ /* No sub-command uses flags at the moment. */
+ if (cmd.flags) {
+ r = -EINVAL;
+ goto out;
+ }
+ if (cmd.id != KVM_SEV_LAUNCH_START &&
+ cmd.id != KVM_SEV_RECEIVE_START && cmd.error64) {
+ r = -EINVAL;
+ goto out;
+ }
+ if ((cmd.id == KVM_SEV_LAUNCH_START ||
+ cmd.id == KVM_SEV_RECEIVE_START) && cmd.error) {
+ r = -EINVAL;
+ goto out;
+ }
+
r = static_call(kvm_x86_mem_enc_ioctl)(kvm, &cmd);
if (copy_to_user(argp, &cmd, sizeof(cmd)))
r = -EFAULT;
--
2.25.1
