Re: [Qemu-devel] [PULL 43/56] sheepdog: Support .bdrv_co_create

[Peter Maydell]

On 9 March 2018 at 16:19, Kevin Wolf <kw...@redhat.com> wrote:
> This adds the .bdrv_co_create driver callback to sheepdog, which enables
> image creation over QMP.
>
> Signed-off-by: Kevin Wolf <kw...@redhat.com>
> Reviewed-by: Max Reitz <mre...@redhat.com>

Hi; Coverity (CID 1390641) points out that the changes to
parse_redundancy_str() introduce a memory leak:

> -static int parse_redundancy_str(BDRVSheepdogState *s, const char *opt)
> +static SheepdogRedundancy *parse_redundancy_str(const char *opt)
>  {
> -    struct SheepdogRedundancy redundancy;
> +    SheepdogRedundancy *redundancy;
>      const char *n1, *n2;
>      long copy, parity;
>      char p[10];
> @@ -1947,26 +1970,27 @@ static int parse_redundancy_str(BDRVSheepdogState *s, 
> const char *opt)
>      n2 = strtok(NULL, ":");
>
>      if (!n1) {
> -        return -EINVAL;
> +        return NULL;
>      }
>
>      ret = qemu_strtol(n1, NULL, 10, &copy);
>      if (ret < 0) {
> -        return ret;
> +        return NULL;
>      }
>
> +    redundancy = g_new0(SheepdogRedundancy, 1);

We now do a memory allocation here...

>      if (!n2) {
> -        redundancy = (SheepdogRedundancy) {
> +        *redundancy = (SheepdogRedundancy) {
>              .type               = SHEEPDOG_REDUNDANCY_TYPE_FULL,
>              .u.full.copies      = copy,
>          };
>      } else {
>          ret = qemu_strtol(n2, NULL, 10, &parity);
>          if (ret < 0) {
> -            return ret;
> +            return NULL;

...but this error-exit path does not free it.

>          }
>
> -        redundancy = (SheepdogRedundancy) {
> +        *redundancy = (SheepdogRedundancy) {
>              .type               = SHEEPDOG_REDUNDANCY_TYPE_ERASURE_CODED,
>              .u.erasure_coded    = {
>                  .data_strips    = copy,
> @@ -1975,17 +1999,19 @@ static int parse_redundancy_str(BDRVSheepdogState *s, 
> const char *opt)
>          };
>      }
>
> -    return parse_redundancy(s, &redundancy);
> +    return redundancy;
>  }

thanks
-- PMM