Re: [libvirt] [PATCH] qemu: avoid dereference of null pointer
On 08/05/2011 12:18 AM, Eric Blake wrote:
On 08/04/2011 09:51 AM, Alex Jia wrote:
> * src/qemu/qemu_driver.c: avoid dereference of null pointer.
>
> Signed-off-by: Alex Jia<ajia(a)redhat.com>
> ---
> src/qemu/qemu_driver.c | 27 ++++++++++++++++++---------
> 1 files changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index ce19be7..28ffff7 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -5697,7 +5697,8 @@ static int
> qemuDomainSetBlkioParameters(virDomainPtr dom,
> continue;
> }
>
> - persistentDef->blkio.weight = params[i].value.ui;
> + if (params[i].value.ul)
> + persistentDef->blkio.weight = params[i].value.ui;
Why check ul, but then use ui? That seems broken.
Ah, correct me, this is a typing
error.
>
> if (flags& VIR_DOMAIN_AFFECT_CONFIG) {
> - vmdef->cputune.quota = params[i].value.l;
> + if (params[i].value.ul)
> + vmdef->cputune.quota = params[i].value.l;
Why check ul, but then use l?
this is also a typing error.
Also, how does checking for a non-zero union value prevent a null
dereference?
To be honest, I'm not sure this, however, it's okay for ccc-analyzer if
I add these judgements,
of course, I'm probably making a mistake, if so, please correct me.
Thanks,
Alex