[PATCH 03/11] KVM: PPC: Book3S HV: Move error code assignments in two functions

From: SF Markus Elfring
Date: Fri Jan 20 2017 - 13:22:18 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Fri, 20 Jan 2017 10:30:26 +0100

A local variable was set to an error code in a few cases before a concrete
error situation was detected. Thus move the corresponding assignments into
if branches to indicate a software failure there.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_hv.c | 25 +++++++++++++++----------
1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 8dcbe37a4dac..a93e1c4445da 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2967,15 +2967,17 @@ static int kvm_vm_ioctl_get_dirty_log_hv(struct kvm *kvm,

mutex_lock(&kvm->slots_lock);

- r = -EINVAL;
- if (log->slot >= KVM_USER_MEM_SLOTS)
+ if (log->slot >= KVM_USER_MEM_SLOTS) {
+ r = -EINVAL;
goto out;
+ }

slots = kvm_memslots(kvm);
memslot = id_to_memslot(slots, log->slot);
- r = -ENOENT;
- if (!memslot->dirty_bitmap)
+ if (!memslot->dirty_bitmap) {
+ r = -ENOENT;
goto out;
+ }

n = kvm_dirty_bitmap_bytes(memslot);
memset(memslot->dirty_bitmap, 0, n);
@@ -2984,9 +2986,10 @@ static int kvm_vm_ioctl_get_dirty_log_hv(struct kvm *kvm,
if (r)
goto out;

- r = -EFAULT;
- if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
+ if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n)) {
+ r = -EFAULT;
goto out;
+ }

r = 0;
out:
@@ -3127,9 +3130,10 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
memslot = gfn_to_memslot(kvm, 0);

/* We must have some memory at 0 by now */
- err = -EINVAL;
- if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
+ if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
+ err = -EINVAL;
goto out_srcu;
+ }

/* Look up the VMA for the start of this memory slot */
hva = memslot->userspace_addr;
@@ -3144,10 +3148,11 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
up_read(&current->mm->mmap_sem);

/* We can handle 4k, 64k or 16M pages in the VRMA */
- err = -EINVAL;
if (!(psize == 0x1000 || psize == 0x10000 ||
- psize == 0x1000000))
+ psize == 0x1000000)) {
+ err = -EINVAL;
goto out_srcu;
+ }

senc = slb_pgsize_encoding(psize);
kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
--
2.11.0