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authorTrond Myklebust <trond.myklebust@hammerspace.com>2020-10-08 00:24:17 +0200
committerAnna Schumaker <Anna.Schumaker@Netapp.com>2020-10-09 16:04:36 +0200
commit1aee551334cda1fed8b8112dbe38257397a55c78 (patch)
tree1d32b4e31a36d59f2568cc14802230bd6cac3baf /fs/nfs
parentNFS: Decode a full READ_PLUS reply (diff)
downloadlinux-1aee551334cda1fed8b8112dbe38257397a55c78.tar.xz
linux-1aee551334cda1fed8b8112dbe38257397a55c78.zip
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>
Diffstat (limited to 'fs/nfs')
-rw-r--r--fs/nfs/nfs4proc.c75
1 files changed, 34 insertions, 41 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d09fd3236820..50a96ca2c385 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -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
@@ -6142,50 +6157,23 @@ nfs4_init_nonuniform_client_string(struct nfs_client *clp)
}
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;
}