| Message ID | 20220819182258.588335-1-vipinsh@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: Fix mce_banks memory leak on mci_ctl2_banks allocation failure | expand |
On Fri, Aug 19, 2022 at 11:23 AM Vipin Sharma <vipinsh@google.com> wrote: > > If mci_ctl2_banks allocation fails, kvm goes to fail_free_pio_data and > forgets about freeing mce_banks memory causing memory leak. > > Individually check memory allocation status and free memory in the correct > order. > > Fixes: 281b52780b57 ("KVM: x86: Add emulation for MSR_IA32_MCx_CTL2 MSRs.") > Signed-off-by: Vipin Sharma <vipinsh@google.com> > --- Reviewed-by: Jim Mattson <jmattson@google.com>
On Fri, Aug 19, 2022, Vipin Sharma wrote: > If mci_ctl2_banks allocation fails, kvm goes to fail_free_pio_data and > forgets about freeing mce_banks memory causing memory leak. > > Individually check memory allocation status and free memory in the correct > order. > > Fixes: 281b52780b57 ("KVM: x86: Add emulation for MSR_IA32_MCx_CTL2 MSRs.") > Signed-off-by: Vipin Sharma <vipinsh@google.com> > --- Pushed to branch `for_paolo/6.1` at: https://github.com/sean-jc/linux.git Unless you hear otherwise, it will make its way to kvm/queue "soon". Note, the commit IDs are not guaranteed to be stable.
On Tue, Aug 30, 2022, Sean Christopherson wrote: > On Fri, Aug 19, 2022, Vipin Sharma wrote: > > If mci_ctl2_banks allocation fails, kvm goes to fail_free_pio_data and > > forgets about freeing mce_banks memory causing memory leak. > > > > Individually check memory allocation status and free memory in the correct > > order. > > > > Fixes: 281b52780b57 ("KVM: x86: Add emulation for MSR_IA32_MCx_CTL2 MSRs.") > > Signed-off-by: Vipin Sharma <vipinsh@google.com> > > --- > > Pushed to branch `for_paolo/6.1` at: > > https://github.com/sean-jc/linux.git > > Unless you hear otherwise, it will make its way to kvm/queue "soon". Doh. Dropping this as Paolo already sent a different fix[*] to Linus, commit 3c0ba05ce9c9 ("KVM: x86: fix memoryleak in kvm_arch_vcpu_create()"). Sorry :-( [*] https://lore.kernel.org/all/20220901122300.22298-1-linmiaohe@huawei.com
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d7374d768296..4b2c7a4f175f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11560,15 +11560,19 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) vcpu->arch.mce_banks = kcalloc(KVM_MAX_MCE_BANKS * 4, sizeof(u64), GFP_KERNEL_ACCOUNT); + if (!vcpu->arch.mce_banks) + goto fail_free_pio_data; + vcpu->arch.mci_ctl2_banks = kcalloc(KVM_MAX_MCE_BANKS, sizeof(u64), GFP_KERNEL_ACCOUNT); - if (!vcpu->arch.mce_banks || !vcpu->arch.mci_ctl2_banks) - goto fail_free_pio_data; + if (!vcpu->arch.mci_ctl2_banks) + goto fail_free_mce_banks; + vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS; if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask, GFP_KERNEL_ACCOUNT)) - goto fail_free_mce_banks; + goto fail_free_mci_ctl2_banks; if (!alloc_emulate_ctxt(vcpu)) goto free_wbinvd_dirty_mask; @@ -11614,9 +11618,10 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt); free_wbinvd_dirty_mask: free_cpumask_var(vcpu->arch.wbinvd_dirty_mask); +fail_free_mci_ctl2_banks: + kfree(vcpu->arch.mci_ctl2_banks); fail_free_mce_banks: kfree(vcpu->arch.mce_banks); - kfree(vcpu->arch.mci_ctl2_banks); fail_free_pio_data: free_page((unsigned long)vcpu->arch.pio_data); fail_free_lapic:
If mci_ctl2_banks allocation fails, kvm goes to fail_free_pio_data and forgets about freeing mce_banks memory causing memory leak. Individually check memory allocation status and free memory in the correct order. Fixes: 281b52780b57 ("KVM: x86: Add emulation for MSR_IA32_MCx_CTL2 MSRs.") Signed-off-by: Vipin Sharma <vipinsh@google.com> --- arch/x86/kvm/x86.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)