[PATCH 11/11] KVM: PPC: Return directly after a failed copy_from_user() in two functions

From: SF Markus Elfring
Date: Fri Jan 20 2017 - 13:30:50 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Fri, 20 Jan 2017 18:00:35 +0100

* Return directly after a call of the function "copy_from_user"
(or two other checks) failed in a case block.

This issue was detected by using the Coccinelle software.

* Delete the jump label "out" which became unnecessary with
this refactoring.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kvm/powerpc.c | 48 ++++++++++++++++++----------------------------
1 file changed, 19 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index efd1183a6b16..7083a680f5fb 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -1256,19 +1256,19 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
switch (ioctl) {
case KVM_INTERRUPT: {
struct kvm_interrupt irq;
- r = -EFAULT;
+
if (copy_from_user(&irq, argp, sizeof(irq)))
- goto out;
+ return -EFAULT;
r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
- goto out;
+ break;
}

case KVM_ENABLE_CAP:
{
struct kvm_enable_cap cap;
- r = -EFAULT;
+
if (copy_from_user(&cap, argp, sizeof(cap)))
- goto out;
+ return -EFAULT;
r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
break;
}
@@ -1277,9 +1277,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
case KVM_GET_ONE_REG:
{
struct kvm_one_reg reg;
- r = -EFAULT;
+
if (copy_from_user(&reg, argp, sizeof(reg)))
- goto out;
+ return -EFAULT;
if (ioctl == KVM_SET_ONE_REG)
r = kvm_vcpu_ioctl_set_one_reg(vcpu, &reg);
else
@@ -1290,9 +1290,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
#if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC)
case KVM_DIRTY_TLB: {
struct kvm_dirty_tlb dirty;
- r = -EFAULT;
+
if (copy_from_user(&dirty, argp, sizeof(dirty)))
- goto out;
+ return -EFAULT;
r = kvm_vcpu_ioctl_dirty_tlb(vcpu, &dirty);
break;
}
@@ -1300,8 +1300,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
default:
r = -EINVAL;
}
-
-out:
return r;
}

@@ -1405,19 +1403,16 @@ long kvm_arch_vm_ioctl(struct file *filp,
struct kvm_ppc_pvinfo pvinfo;
memset(&pvinfo, 0, sizeof(pvinfo));
r = kvm_vm_ioctl_get_pvinfo(&pvinfo);
- if (copy_to_user(argp, &pvinfo, sizeof(pvinfo))) {
- r = -EFAULT;
- goto out;
- }
-
+ if (copy_to_user(argp, &pvinfo, sizeof(pvinfo)))
+ return -EFAULT;
break;
}
case KVM_ENABLE_CAP:
{
struct kvm_enable_cap cap;
- r = -EFAULT;
+
if (copy_from_user(&cap, argp, sizeof(cap)))
- goto out;
+ return -EFAULT;
r = kvm_vm_ioctl_enable_cap(kvm, &cap);
break;
}
@@ -1425,23 +1420,19 @@ long kvm_arch_vm_ioctl(struct file *filp,
case KVM_CREATE_SPAPR_TCE_64: {
struct kvm_create_spapr_tce_64 create_tce_64;

- r = -EFAULT;
if (copy_from_user(&create_tce_64, argp, sizeof(create_tce_64)))
- goto out;
- if (create_tce_64.flags) {
- r = -EINVAL;
- goto out;
- }
+ return -EFAULT;
+ if (create_tce_64.flags)
+ return -EINVAL;
r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce_64);
- goto out;
+ break;
}
case KVM_CREATE_SPAPR_TCE: {
struct kvm_create_spapr_tce create_tce;
struct kvm_create_spapr_tce_64 create_tce_64;

- r = -EFAULT;
if (copy_from_user(&create_tce, argp, sizeof(create_tce)))
- goto out;
+ return -EFAULT;

create_tce_64.liobn = create_tce.liobn;
create_tce_64.page_shift = IOMMU_PAGE_SHIFT_4K;
@@ -1450,7 +1441,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
IOMMU_PAGE_SHIFT_4K;
create_tce_64.flags = 0;
r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce_64);
- goto out;
+ break;
}
case KVM_PPC_GET_SMMU_INFO: {
struct kvm_ppc_smmu_info info;
@@ -1477,7 +1468,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
r = -ENOTTY;
#endif
}
-out:
return r;
}

--
2.11.0