[PATCH] r/o bind mounts: write counts for link/symlink
[AV: add missing nfsd pieces]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 3fbcf20..00df735 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2387,7 +2387,12 @@
if (IS_ERR(dentry))
goto out_unlock;
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
+ mnt_drop_write(nd.path.mnt);
+out_dput:
dput(dentry);
out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
@@ -2482,7 +2487,12 @@
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
goto out_unlock;
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto out_dput;
error = vfs_link(old_nd.path.dentry, nd.path.dentry->d_inode, new_dentry);
+ mnt_drop_write(nd.path.mnt);
+out_dput:
dput(new_dentry);
out_unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 14d5824..71f8994 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1542,6 +1542,10 @@
if (iap && (iap->ia_valid & ATTR_MODE))
mode = iap->ia_mode & S_IALLUGO;
+ host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
+ if (host_err)
+ goto out_nfserr;
+
if (unlikely(path[plen] != 0)) {
char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
if (path_alloced == NULL)
@@ -1562,6 +1566,8 @@
err = nfserrno(host_err);
fh_unlock(fhp);
+ mnt_drop_write(fhp->fh_export->ex_path.mnt);
+
cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
dput(dnew);
if (err==0) err = cerr;
@@ -1612,6 +1618,11 @@
dold = tfhp->fh_dentry;
dest = dold->d_inode;
+ host_err = mnt_want_write(tfhp->fh_export->ex_path.mnt);
+ if (host_err) {
+ err = nfserrno(host_err);
+ goto out_dput;
+ }
host_err = vfs_link(dold, dirp, dnew);
if (!host_err) {
if (EX_ISSYNC(ffhp->fh_export)) {
@@ -1625,7 +1636,8 @@
else
err = nfserrno(host_err);
}
-
+ mnt_drop_write(tfhp->fh_export->ex_path.mnt);
+out_dput:
dput(dnew);
out_unlock:
fh_unlock(ffhp);