Re: [PATCH 09/18] nfsd: implement pNFS operations

Tom Haynes
2015-01-12T17:54:19Z

On Tue, Jan 06, 2015 at 05:28:32PM +0100, Christoph Hellwig wrote:

> +#ifdef CONFIG_NFSD_PNFS
> +static __be32
> +nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
> + struct nfsd4_getdeviceinfo *gdev)
> +{
> + struct xdr_stream *xdr = &resp->xdr;
> + const struct nfsd4_layout_ops *ops =
> + nfsd4_layout_ops[gdev->gd_layout_type];
> + u32 starting_len = xdr->buf->len, needed_len;
> + __be32 *p;
> +
> + dprintk("%s: err %d\n", __func__, nfserr);
> + if (nfserr)
> + goto out;

In nfsd4_block_get_device_info_simple(), gdp->gd_device might have
been allocated, but sb->s_export_op->get_uuid() might have returned
an error, which would cause a leak here.

> +
> + p = xdr_reserve_space(xdr, 4);
> + if (!p)
> + return nfserr_resource;

gdp->gd_device can be leaked here.

> + *p++ = cpu_to_be32(gdev->gd_layout_type);
> +
> + /* If maxcount is 0 then just update notifications */
> + if (gdev->gd_maxcount != 0) {
> + nfserr = ops->encode_getdeviceinfo(xdr, gdev);
> + if (nfserr) {
> + /*
> + * We don't bother to burden the layout drivers with
> + * enforcing gd_maxcount, just tell the client to
> + * come back with a bigger buffer if it's not enough.
> + */
> + if (xdr->buf->len + 4 > gdev->gd_maxcount)
> + goto toosmall;
> + goto out;
> + }
> + }
> +
> + if (gdev->gd_notify_types) {
> + p = xdr_reserve_space(xdr, 4 + 4);
> + if (!p)
> + return nfserr_resource;

gdp->gd_device can be leaked here.

> + *p++ = cpu_to_be32(1); /* bitmap length */
> + *p++ = cpu_to_be32(gdev->gd_notify_types);
> + } else {
> + p = xdr_reserve_space(xdr, 4);
> + if (!p)
> + return nfserr_resource;

gdp->gd_device can be leaked here.

> + *p++ = 0;
> + }
> +
> +out:
> + kfree(gdev->gd_device);
> + dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
> + return nfserr;
> +
> +toosmall:
> + dprintk("%s: maxcount too small\n", __func__);
> + needed_len = xdr->buf->len + 4 /* notifications */;
> + xdr_truncate_encode(xdr, starting_len);
> + p = xdr_reserve_space(xdr, 4);
> + if (!p)
> + return nfserr_resource;
> + *p++ = cpu_to_be32(needed_len);
> + nfserr = nfserr_toosmall;
> + goto out;
> +}
> +