[libvirt] [PATCH] Fix mem leak in virQEMUCapsProbeQMPMachineTypes on OOM

[Michal Privoznik]

On 11.11.2013 12:15, Daniel P. Berrange wrote:
> From: "Daniel P. Berrange" <berrange at redhat.com>
> 
> The virQEMUCapsProbeQMPMachineTypes method iterates over machine
> types copying them into the qemuCapsPtr object. It only updates
> the qemuCaps->nmachinetypes value at the end though. So if OOM
> occurs in the middle, the destructor of qemuCapsPtr will not
> free the partially initialized machine types.
> 
> Signed-off-by: Daniel P. Berrange <berrange at redhat.com>
> ---
>  src/qemu/qemu_capabilities.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
> index 71a913b..2712a4d 100644
> --- a/src/qemu/qemu_capabilities.c
> +++ b/src/qemu/qemu_capabilities.c
> @@ -2137,14 +2137,17 @@ virQEMUCapsProbeQMPMachineTypes(virQEMUCapsPtr qemuCaps,
>          goto cleanup;
>  
>      for (i = 0; i < nmachines; i++) {
> -        if (VIR_STRDUP(qemuCaps->machineAliases[i], machines[i]->alias) < 0 ||
> -            VIR_STRDUP(qemuCaps->machineTypes[i], machines[i]->name) < 0)
> +        qemuCaps->nmachineTypes++;
> +        if (VIR_STRDUP(qemuCaps->machineAliases[qemuCaps->nmachineTypes -1],
> +                       machines[i]->alias) < 0 ||
> +            VIR_STRDUP(qemuCaps->machineTypes[qemuCaps->nmachineTypes - 1],
> +                       machines[i]->name) < 0)
>              goto cleanup;
>          if (machines[i]->isDefault)
>              defIdx = i;
> -        qemuCaps->machineMaxCpus[i] = machines[i]->maxCpus;
> +        qemuCaps->machineMaxCpus[qemuCaps->nmachineTypes - 1] =
> +            machines[i]->maxCpus;
>      }
> -    qemuCaps->nmachineTypes = nmachines;

Wouldn't be sufficient to move this line ^^^ before the for() loop?
Something like we already have in virQEMUCapsNewCopy().

At any rate, this one's good too. ACK.

Michal