2008-06-18 22:32:25

by Chuck Lever III

[permalink] [raw]
Subject: [PATCH 1/4] NFS: Use common device name parsing logic for NFSv4 and NFSv2/v3

To support passing a raw IPv6 address as a server hostname, we need to
expand the logic that handles splitting the passed-in device name into
a server hostname and export path

Start by pulling device name parsing out of the mount option validation
functions and into separate helper functions.

Signed-off-by: Chuck Lever <[email protected]>
---

fs/nfs/super.c | 124 ++++++++++++++++++++++++++++++++++++--------------------
1 files changed, 79 insertions(+), 45 deletions(-)


diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index d884f52..5e0eefa 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1216,6 +1216,67 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
}

/*
+ * Split "dev_name" into "hostname:export_path".
+ *
+ * Note: caller frees hostname and export path, even on error.
+ */
+static int nfs_parse_devname(const char *dev_name,
+ char **hostname, size_t maxnamlen,
+ char **export_path, size_t maxpathlen)
+{
+ size_t len;
+ char *colon, *comma;
+
+ colon = strchr(dev_name, ':');
+ if (colon == NULL)
+ goto out_bad_devname;
+
+ len = colon - dev_name;
+ if (len > maxnamlen)
+ goto out_hostname;
+
+ /* N.B. caller will free nfs_server.hostname in all cases */
+ *hostname = kstrndup(dev_name, len, GFP_KERNEL);
+ if (!*hostname)
+ goto out_nomem;
+
+ /* kill possible hostname list: not supported */
+ comma = strchr(*hostname, ',');
+ if (comma != NULL) {
+ if (comma == *hostname)
+ goto out_bad_devname;
+ *comma = '\0';
+ }
+
+ colon++;
+ len = strlen(colon);
+ if (len > maxpathlen)
+ goto out_path;
+ *export_path = kstrndup(colon, len, GFP_KERNEL);
+ if (!*export_path)
+ goto out_nomem;
+
+ dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
+ return 0;
+
+out_bad_devname:
+ dfprintk(MOUNT, "NFS: device name not in host:path format\n");
+ return -EINVAL;
+
+out_nomem:
+ dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
+ return -ENOMEM;
+
+out_hostname:
+ dfprintk(MOUNT, "NFS: server hostname too long\n");
+ return -ENAMETOOLONG;
+
+out_path:
+ dfprintk(MOUNT, "NFS: export pathname too long\n");
+ return -ENAMETOOLONG;
+}
+
+/*
* Validate the NFS2/NFS3 mount data
* - fills in the mount root filehandle
*
@@ -1341,8 +1402,6 @@ static int nfs_validate_mount_data(void *options,

break;
default: {
- unsigned int len;
- char *c;
int status;

if (nfs_parse_mount_options((char *)options, args) == 0)
@@ -1357,21 +1416,17 @@ static int nfs_validate_mount_data(void *options,

nfs_set_transport_defaults(args);

- c = strchr(dev_name, ':');
- if (c == NULL)
- return -EINVAL;
- len = c - dev_name;
- /* N.B. caller will free nfs_server.hostname in all cases */
- args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
- if (!args->nfs_server.hostname)
- goto out_nomem;
+ status = nfs_parse_devname(dev_name,
+ &args->nfs_server.hostname,
+ PAGE_SIZE,
+ &args->nfs_server.export_path,
+ NFS_MAXPATHLEN);
+ if (!status)
+ status = nfs_try_mount(args, mntfh);

- c++;
- if (strlen(c) > NFS_MAXPATHLEN)
- return -ENAMETOOLONG;
- args->nfs_server.export_path = c;
+ kfree(args->nfs_server.export_path);
+ args->nfs_server.export_path = NULL;

- status = nfs_try_mount(args, mntfh);
if (status)
return status;

@@ -1898,7 +1953,7 @@ static int nfs4_validate_mount_data(void *options,

break;
default: {
- unsigned int len;
+ int status;

if (nfs_parse_mount_options((char *)options, args) == 0)
return -EINVAL;
@@ -1922,34 +1977,17 @@ static int nfs4_validate_mount_data(void *options,
goto out_inval_auth;
}

- /*
- * Split "dev_name" into "hostname:mntpath".
- */
- c = strchr(dev_name, ':');
- if (c == NULL)
- return -EINVAL;
- /* while calculating len, pretend ':' is '\0' */
- len = c - dev_name;
- if (len > NFS4_MAXNAMLEN)
- return -ENAMETOOLONG;
- /* N.B. caller will free nfs_server.hostname in all cases */
- args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
- if (!args->nfs_server.hostname)
- goto out_nomem;
-
- c++; /* step over the ':' */
- len = strlen(c);
- if (len > NFS4_MAXPATHLEN)
- return -ENAMETOOLONG;
- args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
- if (!args->nfs_server.export_path)
- goto out_nomem;
-
- dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
-
if (args->client_address == NULL)
goto out_no_client_address;

+ status = nfs_parse_devname(dev_name,
+ &args->nfs_server.hostname,
+ NFS4_MAXNAMLEN,
+ &args->nfs_server.export_path,
+ NFS4_MAXPATHLEN);
+ if (status < 0)
+ return status;
+
break;
}
}
@@ -1965,10 +2003,6 @@ out_inval_auth:
data->auth_flavourlen);
return -EINVAL;

-out_nomem:
- dfprintk(MOUNT, "NFS4: not enough memory to handle mount options\n");
- return -ENOMEM;
-
out_no_address:
dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
return -EINVAL;