[libvirt] [PATCH] remote: fix jump depends on uninitialised value

[Michal Privoznik]

On 24.10.2014 06:03, Jincheng Miao wrote:
> Currently remote driver only initializes partial fields of
> remote_connect_get_all_domain_stats_args. But xdr_array()
> will check the uninitialised field 'doms_val'.
> For safty reason, memset all fields of args is better.
>
> Fix the following error from valgrind, like:
> ==30515== 1 errors in context 1 of 3:
> ==30515== Conditional jump or move depends on uninitialised value(s)
> ==30515==    at 0x85E9402: xdr_array (xdr_array.c:88)
> ==30515==    by 0x4FD8FC9: xdr_remote_connect_get_all_domain_stats_args (remote_protocol.c:6473)
> ==30515==    by 0x4FE72F2: virNetMessageEncodePayload (virnetmessage.c:350)
> ==30515==    by 0x4FDD21C: virNetClientProgramCall (virnetclientprogram.c:326)
> ==30515==    by 0x4FB4D01: callFull.isra.2 (remote_driver.c:6667)
> ==30515==    by 0x4FCBD45: call (remote_driver.c:6689)
> ==30515==    by 0x4FCBD45: remoteConnectGetAllDomainStats (remote_driver.c:7793)
> ==30515==    by 0x4FA0E75: virConnectGetAllDomainStats (libvirt.c:21678)
> ==30515==    by 0x147FD1: cmdDomstats (virsh-domain-monitor.c:2148)
> ==30515==    by 0x13006B: vshCommandRun (virsh.c:1915)
> ==30515==    by 0x12A9E1: main (virsh.c:3699)
>
> Signed-off-by: Jincheng Miao <jmiao at redhat.com>
> ---
>   src/remote/remote_driver.c |    2 ++
>   1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
> index 067f2d0..b8d90ed 100644
> --- a/src/remote/remote_driver.c
> +++ b/src/remote/remote_driver.c
> @@ -7779,6 +7779,8 @@ remoteConnectGetAllDomainStats(virConnectPtr conn,
>       virDomainStatsRecordPtr elem = NULL;
>       virDomainStatsRecordPtr *tmpret = NULL;
>
> +    memset(&args, 0, sizeof(args));
> +
>       if (ndoms) {
>           if (VIR_ALLOC_N(args.doms.doms_val, ndoms) < 0)
>               goto cleanup;
>

ACked and pushed. Nice catch!

Michal