nfsd: make V4ROOT exports read-only
I can't see any use for writeable V4ROOT exports.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 18ac20f..7d5ba1b 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -355,7 +355,7 @@
struct svc_export *old);
static struct svc_export *svc_export_lookup(struct svc_export *);
-static int check_export(struct inode *inode, int flags, unsigned char *uuid)
+static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
{
/*
@@ -367,6 +367,13 @@
!S_ISREG(inode->i_mode))
return -ENOTDIR;
+ /*
+ * Mountd should never pass down a writeable V4ROOT export, but,
+ * just to make sure:
+ */
+ if (*flags & NFSEXP_V4ROOT)
+ *flags |= NFSEXP_READONLY;
+
/* There are two requirements on a filesystem to be exportable.
* 1: We must be able to identify the filesystem from a number.
* either a device number (so FS_REQUIRES_DEV needed)
@@ -375,7 +382,7 @@
* This means that s_export_op must be set.
*/
if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
- !(flags & NFSEXP_FSID) &&
+ !(*flags & NFSEXP_FSID) &&
uuid == NULL) {
dprintk("exp_export: export of non-dev fs without fsid\n");
return -EINVAL;
@@ -590,7 +597,7 @@
goto out4;
}
- err = check_export(exp.ex_path.dentry->d_inode, exp.ex_flags,
+ err = check_export(exp.ex_path.dentry->d_inode, &exp.ex_flags,
exp.ex_uuid);
if (err)
goto out4;
@@ -1029,7 +1036,7 @@
goto finish;
}
- err = check_export(path.dentry->d_inode, nxp->ex_flags, NULL);
+ err = check_export(path.dentry->d_inode, &nxp->ex_flags, NULL);
if (err) goto finish;
err = -ENOMEM;