Re: [PATCH] fix memory leak on kvm_vm_ioctl_create_spapr_tce

From: David Hildenbrand
Date: Tue Aug 22 2017 - 11:16:04 EST


On 22.08.2017 16:28, nixiaoming wrote:
> miss kfree(stt) when anon_inode_getfd return fail
> so add check anon_inode_getfd return val, and kfree stt
>
> Signed-off-by: nixiaoming <nixiaoming@xxxxxxxxxx>
> ---
> arch/powerpc/kvm/book3s_64_vio.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
> index a160c14..a0b4459 100644
> --- a/arch/powerpc/kvm/book3s_64_vio.c
> +++ b/arch/powerpc/kvm/book3s_64_vio.c
> @@ -341,8 +341,11 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
>
> mutex_unlock(&kvm->lock);
>
> - return anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
> + ret = anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
> stt, O_RDWR | O_CLOEXEC);
> + if (ret < 0)
> + goto fail;
> + return ret;
>
> fail:
> if (stt) {
>


stt has already been added to kvm->arch.spapr_tce_tables, so freeing it
is evil IMHO. I don't know that code, so I don't know if there is some
other place that will make sure that everything in
kvm->arch.spapr_tce_tables will properly get freed, even when no release
function has been called (kvm_spapr_tce_release).
--

Thanks,

David