Re: [Qemu-devel] [PATCH] 9pfs: fix memory leak in v9fs_xattrcreate

[Greg Kurz <groug@kaod.org>]

On Mon, 10 Oct 2016 03:41:38 -0700
Li Qiang <liq3ea@gmail.com> wrote:

> From: Li Qiang <liqiang6-s@360.cn>
> 
> The 'fs.xattr.value' field in V9fsFidState object doesn't consider the
> situation that this field has been allocated previously. Every time, it
> will be allocated directly. This leads a host memory leak issue. This
> patch fix this.
> 
> Signed-off-by: Li Qiang <liqiang6-s@360.cn>
> ---

I'll add to the changelog that this may happen if the client sends a
Txattrcreate message with the same fid number before the fid was
clunked.

Reviewed-by: Greg Kurz <groug@kaod.org>

>  hw/9pfs/9p.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> index 8751c19..e4040dc 100644
> --- a/hw/9pfs/9p.c
> +++ b/hw/9pfs/9p.c
> @@ -3282,6 +3282,7 @@ static void v9fs_xattrcreate(void *opaque)
>      xattr_fidp->fs.xattr.flags = flags;
>      v9fs_string_init(&xattr_fidp->fs.xattr.name);
>      v9fs_string_copy(&xattr_fidp->fs.xattr.name, &name);
> +    g_free(xattr_fidp->fs.xattr.value);
>      xattr_fidp->fs.xattr.value = g_malloc0(size);
>      err = offset;
>      put_fid(pdu, file_fidp);