[libvirt] [PATCH 06/19] qemu_agent: Resolve Coverity RESOURCE_LEAK

[Wang Rui]

On 2014/8/28 4:54, John Ferlan wrote:
> Coverity found that on error paths, the 'arg' value wasn't be cleaned
> up. Followed the example in qemuAgentSetVCPUs() where upon successful call
> to qemuAgentCommand() the 'cpus' is set to NULL; otherwise, when cleanup
> occurs the free the memory for 'arg'
> 
> Signed-off-by: John Ferlan <jferlan at redhat.com>
> ---
>  src/qemu/qemu_agent.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/src/qemu/qemu_agent.c b/src/qemu/qemu_agent.c
> index a10954a..fe38f6d 100644
> --- a/src/qemu/qemu_agent.c
> +++ b/src/qemu/qemu_agent.c
> @@ -1328,7 +1328,7 @@ int qemuAgentFSFreeze(qemuAgentPtr mon, const char **mountpoints,
>                        unsigned int nmountpoints)
>  {
>      int ret = -1;
> -    virJSONValuePtr cmd, arg;
> +    virJSONValuePtr cmd, arg = NULL;
>      virJSONValuePtr reply = NULL;
>  
>      if (mountpoints && nmountpoints) {
> @@ -1343,7 +1343,8 @@ int qemuAgentFSFreeze(qemuAgentPtr mon, const char **mountpoints,
>      }
>  
>      if (!cmd)
> -        return -1;
> +        goto cleanup;
> +    arg = NULL;

Setting arg to NULL can also lead to memory leak.
It makes virJSONValueFree(arg) below invalid.

>  
>      if (qemuAgentCommand(mon, cmd, &reply, true,
>                           VIR_DOMAIN_QEMU_AGENT_COMMAND_BLOCK) < 0)
> @@ -1355,6 +1356,7 @@ int qemuAgentFSFreeze(qemuAgentPtr mon, const char **mountpoints,
>      }
>  
>   cleanup:
> +    virJSONValueFree(arg);
>      virJSONValueFree(cmd);
>      virJSONValueFree(reply);
>      return ret;