KVM: Use memdup_user instead of kmalloc/copy_from_user
Switch to using memdup_user when possible. This makes code more
smaller and compact, and prevents errors.
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a6e612f..d8bac07 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1821,12 +1821,11 @@
struct kvm_regs *kvm_regs;
r = -ENOMEM;
- kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
- if (!kvm_regs)
+ kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
+ if (IS_ERR(kvm_regs)) {
+ r = PTR_ERR(kvm_regs);
goto out;
- r = -EFAULT;
- if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
- goto out_free2;
+ }
r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
if (r)
goto out_free2;
@@ -1850,13 +1849,11 @@
break;
}
case KVM_SET_SREGS: {
- kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
- r = -ENOMEM;
- if (!kvm_sregs)
+ kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
+ if (IS_ERR(kvm_sregs)) {
+ r = PTR_ERR(kvm_sregs);
goto out;
- r = -EFAULT;
- if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
- goto out;
+ }
r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
if (r)
goto out;
@@ -1952,13 +1949,11 @@
break;
}
case KVM_SET_FPU: {
- fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
- r = -ENOMEM;
- if (!fpu)
+ fpu = memdup_user(argp, sizeof(*fpu));
+ if (IS_ERR(fpu)) {
+ r = PTR_ERR(fpu);
goto out;
- r = -EFAULT;
- if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
- goto out;
+ }
r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
if (r)
goto out;