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: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Trond Myklebust 2020-10-07 18:24:17 -04:00 committed by Anna Schumaker
parent bff049a3b5
commit 1aee551334

View file

@ -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;
@ -6198,9 +6186,14 @@ nfs4_init_uniform_client_string(struct nfs_client *clp)
if (!str)
return -ENOMEM;
scnprintf(str, len, "Linux NFSv%u.%u %s",
clp->rpc_ops->version, clp->cl_minorversion,
clp->cl_rpcclient->cl_nodename);
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);
clp->cl_owner_id = str;
return 0;
}