Commit 1aee5513 authored by Trond Myklebust's avatar Trond Myklebust Committed by Anna Schumaker
Browse files

NFSv4: Clean up initialisation of uniquified client id strings 



When the user sets a uniquifier, then ensure we copy the string
so that calls to strlen() etc are atomic with calls to snprintf().

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent bff049a3

fs/nfs/nfs4proc.c

+34 −41
Original line number Diff line number Diff line
@@ -6093,9 +6093,22 @@ static void nfs4_init_boot_verifier(const struct nfs_client *clp, 
	memcpy(bootverf->data, verf, sizeof(bootverf->data));

}



static size_t

nfs4_get_uniquifier(char *buf, size_t buflen)

{

	buf[0] = '\0';



	if (nfs4_client_id_uniquifier[0] != '\0')

		strscpy(buf, nfs4_client_id_uniquifier, buflen);



	return strlen(buf);

}



static int

nfs4_init_nonuniform_client_string(struct nfs_client *clp)

{

	char buf[NFS4_CLIENT_ID_UNIQ_LEN];

	size_t buflen;

	size_t len;

	char *str;
@@ -6109,8 +6122,11 @@ nfs4_init_nonuniform_client_string(struct nfs_client *clp) 
		strlen(rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR)) +

		1;

	rcu_read_unlock();

	if (nfs4_client_id_uniquifier[0] != '\0')

		len += strlen(nfs4_client_id_uniquifier) + 1;



	buflen = nfs4_get_uniquifier(buf, sizeof(buf));

	if (buflen)

		len += buflen + 1;



	if (len > NFS4_OPAQUE_LIMIT + 1)

		return -EINVAL;
@@ -6124,10 +6140,9 @@ nfs4_init_nonuniform_client_string(struct nfs_client *clp) 
		return -ENOMEM;



	rcu_read_lock();

	if (nfs4_client_id_uniquifier[0] != '\0')

	if (buflen)

		scnprintf(str, len, "Linux NFSv4.0 %s/%s/%s",

			  clp->cl_rpcclient->cl_nodename,

			  nfs4_client_id_uniquifier,

			  clp->cl_rpcclient->cl_nodename, buf,

			  rpc_peeraddr2str(clp->cl_rpcclient,

					   RPC_DISPLAY_ADDR));

	else
@@ -6141,51 +6156,24 @@ nfs4_init_nonuniform_client_string(struct nfs_client *clp) 
	return 0;

}



static int

nfs4_init_uniquifier_client_string(struct nfs_client *clp)

{

	size_t len;

	char *str;



	len = 10 + 10 + 1 + 10 + 1 +

		strlen(nfs4_client_id_uniquifier) + 1 +

		strlen(clp->cl_rpcclient->cl_nodename) + 1;



	if (len > NFS4_OPAQUE_LIMIT + 1)

		return -EINVAL;



	/*

	 * Since this string is allocated at mount time, and held until the

	 * nfs_client is destroyed, we can use GFP_KERNEL here w/o worrying

	 * about a memory-reclaim deadlock.

	 */

	str = kmalloc(len, GFP_KERNEL);

	if (!str)

		return -ENOMEM;



	scnprintf(str, len, "Linux NFSv%u.%u %s/%s",

			clp->rpc_ops->version, clp->cl_minorversion,

			nfs4_client_id_uniquifier,

			clp->cl_rpcclient->cl_nodename);

	clp->cl_owner_id = str;

	return 0;

}



static int

nfs4_init_uniform_client_string(struct nfs_client *clp)

{

	char buf[NFS4_CLIENT_ID_UNIQ_LEN];

	size_t buflen;

	size_t len;

	char *str;



	if (clp->cl_owner_id != NULL)

		return 0;



	if (nfs4_client_id_uniquifier[0] != '\0')

		return nfs4_init_uniquifier_client_string(clp);



	len = 10 + 10 + 1 + 10 + 1 +

		strlen(clp->cl_rpcclient->cl_nodename) + 1;



	buflen = nfs4_get_uniquifier(buf, sizeof(buf));

	if (buflen)

		len += buflen + 1;



	if (len > NFS4_OPAQUE_LIMIT + 1)

		return -EINVAL;
@@ -6198,6 +6186,11 @@ nfs4_init_uniform_client_string(struct nfs_client *clp) 
	if (!str)

		return -ENOMEM;



	if (buflen)

		scnprintf(str, len, "Linux NFSv%u.%u %s/%s",

			  clp->rpc_ops->version, clp->cl_minorversion,

			  buf, clp->cl_rpcclient->cl_nodename);

	else

		scnprintf(str, len, "Linux NFSv%u.%u %s",

			  clp->rpc_ops->version, clp->cl_minorversion,

			  clp->cl_rpcclient->cl_nodename);